Spurs twice came from behind in their efforts to end a run of six consecutive semi-final defeats, with goals from Harry Kane and Dele Alli cancelling out a first-half Willian brace.
However, Eden Hazard came off the bench to restore Chelsea's lead once more before Nemanja Matic capped off the scoring in stunning fashion 10 minutes from time.
Find out how it all unfolded in an action-packed London derby courtesy of Sports Mole's minute-by-minute updates below.
4.15pmGood afternoon! Thank you very much for joining Sports Mole for today's mouth-watering FA Cup semi-final between Chelsea and Tottenham Hotspur at Wembley! These are always special occasions, and this particular match is one that would be fitting of the final itself. The two best teams in England go head to head and put their ongoing title battle on hold for one afternoon only knowing that a showdown against either Arsenal or Manchester City awaits the winner. Before we have a closer look, though, let's check out the team news...
4.17pmCHELSEA STARTING XI: Courtois; Azpilicueta, David Luiz, Ake; Moses, Kante, Matic, Alonso; Willian, Batshuayi, Pedro
4.17pmCHELSEA SUBS: Begovic, Zouma, Terry, Chalobah, Fabregas, Hazard, Diego Costa
4.21pmSome verrrrryyy interesting selections from Chelsea there as Antonio Conte opts to name something of a weakened side for this match in contrast to Pochettino - a hint perhaps at the priorities of both clubs over the closing stages of the season. The headline news as far as Chelsea are concerned is that Diego Costa and Eden Hazard both miss out, dropping to the bench as Cote rests his two most dangerous attacking players. Costa's recent form had been questioned, but the decision to also leave Hazard out is a surprising one from the Italian.
4.23pmCosta's absence means that Michy Batshuayi will get a rare chance to impress while leading the line - just his sixth start in any competition since joining the club. Willian also comes in for Hazard, leaving Pedro as the only member of that front three to retain his spot. The Spaniard has scored four goals and assisted two more in his three FA Cup appearances this season, though, so there is still firepower for the Blues to rely on even with Costa and Hazard on the bench.
4.25pmThe majority of the pre-match team talk surrounded the availability of Gary Cahill, but as expected the on-field captain for the season misses out having been treated for gastroenteritis earlier this week. Zouma and Terry, the latter of whom recently announced that he will leave the club at the end of the season, may have been hopeful of a recall, but Conte has instead opted for Nathan Ake, who has barely had a look-in since seeing his loan spell at Bournemouth cut short earlier this season.
4.27pmIn all, Conte has made five changes to the side that was beaten by Manchester United six days ago, including returns for Thibaut Courtois and Marcos Alonso from an ankle injury and illness respectively. That means that Chelsea are back to what has become their first-choice midfield quartet of Moses, Kante, Matic and Alonso, with Fabregas once again having to settle for a place on the bench from the start. Azpilicueta, meanwhile, returns to the back three having played as a wing-back at Old Trafford.
4.29pmUnlike Chelsea, Spurs have decided not to make a host of changes for this one, naming more or less a full-strength side for today's game. The only exceptions to that would probably be in defence, where it looks as though Vertonghen will play as left-back, with Davies dropping to the bench and Rose still not quite ready to return following a knee injury. There had been suggestions that Spurs would switch to three at the back to match up against Chelsea - as they did in the Premier League win at White Hart Lane - but it doesn't appear as though that is the case.
4.31pmWith Dier, Alderweireld and Vertonghen all playing it is possible that Spurs could play three at the back, but that would mean one of Son, Eriksen or Alli playing as a left-wing-back, which is highly unlikely considering the recent form of that trio. All three have been scintillating during Tottenham's recent purple patch, not least Son, who has scored eight goals in his last six appearances for the club across all competitions.
4.33pmSon has actually directly contributed to more FA Cup goals than any other player in the competition this season, scoring a joint-high six goals and assisting another. That includes a hat-trick in the last round against Millwall, while Harry Kane hit a treble in the round before that to fire Spurs past Fulham. There is plenty of firepower in that attacking lineup for Spurs, then, and Pochettino has resisted the temptation to rest his star attacking players, with Kane leading the line once again.
4.35pmPochettino has made just two changes to the side that swept Bournemouth aside last weekend, with Trippier replacing Walker at right-back and Wanyama coming in for Davies, allowing Dier to drop back into central defence. Trippier in particular has performed very well when he has been given a chance recently, earning a man of the match award in his last outing, and this will be another chance for him to stake his claim for more regular appearances. Hugo Lloris, meanwhile, starts in goal for his first FA Cup appearance since 2014 due to a knee injury for Vorm.
4.37pmAn already fascinating contest is made even more interesting by those team selections, though, and it could be the case that there is more than just a place in the FA Cup final to fight for today. Victory for either side could see them gain a psychological edge in the Premier League title race - a race which Chelsea still lead but which is also a lot more open now than it was just a few weeks ago. At the start of April Chelsea boasted a 10-point lead at the top of the table, whereas now that lead stands at four points.
4.39pmThe gap has been cut due to a couple of unexpected slip-ups from Chelsea, who before that had looked unstoppable on their way to the title. Conte's side have now lost two of their last four outings - as many as they had lost in their previous 27 across all competitions - and appear to be wavering under a bit of pressure from Spurs. Defeats to Crystal Palace and Manchester United - the latter of which saw them fail to have a single shot on target - mean that they have already lost as many games this months as they had in their previous six months.
4.41pmIs the pressure getting to Chelsea, then? Well, even when they were still picking up regular points there were one or two signs that pointed to them not quite being the force they were when they embarked on a record-equalling winning streak earlier in the campaign. Perhaps the biggest of those is their lack of clean sheets recently - Chelsea have now gone 10 Premier League games without one having kept 12 in their previous 16 outings before that.
4.43pmIndeed, all of Chelsea's last three clean sheets have come in this competition, stretching back exactly three months. The Blues have kept three consecutive FA Cup clean sheets on their way to the semi-finals, with the only goal they have conceded in this season's competition coming at the hands of Peterborough United in the third round. They have scored 11 goals in that time too, cruising past Peterborough (4-1), Brentford (4-0) and Wolves (2-0) before coming up against Manchester United in the last round.
4.45pmThat, predictably, proved to be Chelsea's sternest test so far in this season's competition, but they were helped by a red card for Ander Herrera with 10 minutes still left in the first half and an N'Golo Kante strike after the interval proved to be enough for them to progress. United did get a measure of revenge for that defeat last Sunday, however, with Herrera scoring one and creating another as they ran out 2-0 winners at Old Trafford.
4.47pmChelsea have not lost back-to-back matches yet under Antonio Conte, last suffering that fate more than a year ago with consecutive defeats at the hands of Swansea and Manchester City, but this is a tricky period of the season for them. With Spurs breathing down their necks Chelsea must take on Southampton and Everton as well as this game against the Lilywhites over the next eight days. Defeat today would of course not have an impact on their lead in the league, but it could well put even more pressure on their shoulders to return to form against the Saints at Stamford Bridge in midweek.
4.49pmChelsea have only lost one of their last five FA Cup semi-finals, although that was their most recent appearance at this stage - losing to Manchester City in 2013. They are seven-time winners of the competition in all, and remarkable six of those triumphs have come since Tottenham - one of only three teams to have won the competition more times than Chelsea - last lifted the trophy. Chelsea have also lost two of their last three games at Wembley, although the exception did come against Spurs when they triumphed in the 2015 League Cup final.
4.51pmWhen it comes to Wembley woes it is Tottenham who take the prize ahead of Chelsea, with Pochettino's side have struggled at the national stadium this season and stretching even further back. Since beating Chelsea in the final of the 2008 League Cup, Spurs have won just one of their eight outings at Wembley, drawing two and losing five of those. It is an issue that will need to be resolved if, as expected, Tottenham are to make Wembley their home ground while the new White Hart Lane is being completed next season.
4.53pmMauricio Pochettino has repeatedly insisted that there is no Wembley curse for his side, but there is clearly something amiss when compared with their form at White Hart Lane. Spurs have been nigh-on unstoppable at their usual home this season, winning 19 and drawing two of their 21 outings at the Lane, but in their European home matches - being played at Wembley this season - they have won just one and lost two of their four games - form which saw them eliminated from the Champions League in the group stages and then the Europa League at the first hurdle.
4.55pmIndeed, the last time Spurs failed to win a match was their last outing at Wembley, drawing 2-2 with Gent in February to confirm their exit from the Europa League. Since that disappointing result, Spurs have won eight matches on the bounce - their best run since a 13-match winning streak between April and October in 1960 and the second-best run in the club's history. It is that imperious form that has many tipping them as slight favourites for this match and it is also what has kept them in the Premier League title race.
4.57pmSpurs haven't just been winning the majority of those games, though, they have been blowing teams away too. They come into today's match off the back of consecutive 4-0 victories over Watford and Bournemouth respectively, while during their eight-match winning streak they have scored 28 goals - an average of 3.5 per match. Coupled with a defence which is the best in the Premier League, it is easy to see how Spurs have come up with such a dangerous winning formula of late.
4.59pmWorryingly for Chelsea, Tottenham's goalscoring rate is even better in the FA Cup this season, with 15 goals from four outings on their way to the semi-finals. This is, however, the first time that they have come up against Premier League opposition in that time, with wins over Aston Villa, Wycombe Wanderers, Fulham and Millwall in the previous rounds. Spurs have conceded more goals than Chelsea in this season's competition - 3 - but they have also kept the same number of clean sheets too.
5.01pmAll three of those goals were conceded in their thrilling fourth-round victory over Wycombe Wanderers, but that is the only real scare Spurs have had along the way. The quarter-final turned out to be the easiest one of the lot for Pochettino's side as they thrashed Millwall 6-0, with Son grabbing a hat-trick and Eriksen, Alli and Janssen also on the scoresheet in the London derby.
5.03pmHowever, Tottenham's record when they get to this stage of the competition is dreadful over recent years. They have lost their last six FA Cup semi-finals, equalling the record of Chelsea between 1920 and 1966, and another defeat today would see them take sole control of that unwanted landmark. The last time they were victorious at this stage was in 1991, beating Arsenal 3-1 on their way to lifting the trophy for the eighth time. At that point they were the most successful team in the competition's history, but they have since been overtaken by Arsenal and Manchester United, who have won the competitions seven times and five times since Tottenham's last triumph.
5.05pmPREDICTION: Right, we're 10 minutes away from kickoff at Wembley, which means that it is time for a prediction! This match really could go either way and it will be fascinating to watch, but the team selections just gives the edge to Tottenham as far as I am concerned. They come into the match in better form and have named all of their star players, so I'm backing Pochettino's side to emerge victors - quite possibly via extra time.
5.07pmChelsea have traditionally dominated this fixture since the turn of the century, but things have evened up a bit in recent years and the last six meetings have been split evenly at two wins apiece and two draws. Looking further back, though, those are Tottenham's only two wins in the last 16 meetings across all competitions (D7 L7), although one of those did come in the most recent clash.
5.09pmThese two sides met in January with Chelsea in record-breaking form, but the irresistible force crashed into the immovable object and it was Tottenham that emerged victorious with a 2-0 victory at White Hart Lane courtesy of a Dele Alli brace. The last time they met here at Wembley was in that 2015 League Cup final, and on that occasion it was Chelsea who ran out 2-0 winners, with Terry and Costa getting the goals.
5.11pmThis will be the 12th meeting between these two sides in the FA Cup, the most recent of which was also a semi-final back in 2012. That turned into a day to forget for Spurs, though, as they were thrashed 5-1 on Chelsea's way to the trophy, with five different Chelsea players on the scoresheet. Spurs are winless in their last four FA Cup games against their West London rivals, a run which stretches back to a 3-2 quarter-final triumph at Stamford Bridge in 1982.
5.13pmRight, the players are on their way out to a brilliant atmosphere at Wembley. Before kickoff, tributes will be paid to Ugo Ehiogu - the former England international and Tottenham Under-23 coach who tragically passed away at the age of just 44 this week.
1 minKICKOFF: Wembley applaud as one to remember Ehiogu, and a huge roar greets the whistle that brings the minute to a close. Now it's game time, and Tottenham get us underway.
3 minYELLOW CARD! Quick start from Chelsea as they look to get on the front foot early. Alderweireld is forced into a risky challenge that sees him scythe down Pedro on the edge of the box, which earns him a yellow. It may have been even worse with a harsher ref...
5 minGOAL! Chelsea 1-0 Tottenham Hotspur (Willian)
5 minWhat a start for Chelsea! They take the lead after just five minutes, and it is a fine opening goal from Willian too! He lines up the free kick from Alderweireld's challenge and curls it right into the far corner, past Lloris on the goalkeeper's side. The Spurs skipper was unsighted by his wall and took a step to his right before the shot arrived so may well feel that he should have done better there - take nothing away from that strike, though!
7 minSemi-finals can often be cagey affairs - and this stadium in particular has seen its fair share - but it has been a charged opening to this match and that early goal has set this one up very nicely. Spurs must attack now!
9 minThat free kick looked like it took a small deflection on the way through, but Lloris wouldn't have been anywhere near it in any event. Lloris didn't really seem to be covering either side of the goal there!
11 minA plane is flying above Wembley carrying the message 'Antonio! Antonio! with a Chelsea flag. They love the Italian in West London, and it is easy to see why - as things stand they are still on course for a double in his debut season.
15 minGood football from Chelsea as they come forward down the right flank through Pedro. His cross is blocked before Williannocks it back to Kante, who picks out an unmarked Batshuayi in the area. It would be a clear chance for the striker, but the linesman's flag is raised and his header - which was comfortably saved by Lloris anyway - would not have counted.
17 minSpurs have their first hint of a sight of goal as Eriksen plays a clever quick free kick into the feet of Kane just inside the area. Kante is alert to the danger, though, and deflects the eventual shot behind for a corner.
18 minGOAL! Chelsea 1-1 Tottenham Hotspur (Harry Kane)
18 minWe could be in for a good game here today, folks! This one is already living up to the billing as Spurs equalised with less than 20 minutes on the clock. It is another fine goal too, if very different from Willian's strike. The initial corner is cleared out, but Eriksen picks up the ball on the right flank and creates space to whip it back into the middle with his left foot. Kane still has a lot to do, but he flicks a clever backward header right into the far corner.
20 minSpurs have another chance to get the ball into the box here following an untidy challenge from Alonso, who slipped into it...
21 min...this time Eriksen's delivery comes to nothing, though, as Batshuayi gets it clear.
23 minThat goal has really made a difference for Spurs, who were a bit slow to get going in this match but now look to be on top. Midway through the first half and we have already seen plenty of action here.
25 minThere is concern over David Luiz here as the Brazilian looks to be in a lot of pain after Alli accidentally trod on his ankle. Terry is sent out to warm up, but Luiz should be fine to continue.
27 minChelsea are a little unfortunate not to be awarded a penalty or at least a free kick right on the edge of the box as Dembele rather unceremoniously moves Willian out the way to get the ball. Not a lot was made of it, but had it not been in such a dangerous area that may well have been given.
29 minThe Tottenham fans are in fine voice as they chant Dele Alli's name around Wembley. Nothing much to report in terms of chances aside from the two goals, but that is not to say that this has been dull.
31 minSpurs are seeing more of the ball right now as they continue to probe for a way through the Chelsea defence again. Incidentally, Tottenham are playing three at the back now, with Son filling in as the left wing-back.
35 minCrucial interception from Kante to stop Eriksen's delivery from reaching Son. The South Korean had just lost his marker from a free kick and was lining up to sweep the ball home, but Kante puts it behind for a corner.
36 minCLOSE! Moments after Wanyama is unable to react in time when in a good place Spurs hoist another ball into the box, with Vertonghen whipping a beauty in from the left flank. Dier is still up there from the corner and glances his header just wide of the far post.
38 minThis time it is Luiz who needs to make an important defensive contribution as he hooks the ball away from Alli after a good flick-on from Kane. Had Luiz not got to that then Alli would have been clean through on goal.
40 minSAVE! Some sloppy play at the back from Chelsea forces a mistake as Azpilicueta gives the ball straight to Eriksen when trying to clear the danger. Eriksen lines up a shot from range, but curls it straight into the arms of Courtois.
42 minNightmare for Spurs right on the stroke of half time as Son slides in on Moses inside the area and brings the wing-back down. Moses jumped over the challenge, but it was a stupid tackle from Son and without Moses's evasive action then it would have been a clear foul.
43 minGOAL! Chelsea 2-1 Tottenham Hotspur (Willian, penalty)
43 minAfter a brief discussion to decide who will take it, Willian gets the nod and holds his nerve to send Lloris the wrong way. Two dead-ball goals from Willian and Chelsea look like taking the lead into half time now!
45 minSpurs are looking a little bit nervy here and Lloris gets away with one here. He comes out to claim the ball and, in doing so, carries it outside his penalty area. He nudges it back in with his hands before collecting, and none of the officials seem to have noticed the handball. Lloris is a lucky man there!
45+1 minThere will be two minutes of added time at the end of this first half.
45+3 minYELLOW CARD! Alonso picks up an unnecessary yellow card in the dying embers of the first half here.
6.14pmMartin Atkinson brings an end to an entertaining first half at Wembley, then, and it is Chelsea who have the lead at the halfway stage of this semi-final. These games are often cagey affairs, but that has not been the case so far today and we are set up for a brilliant coming 45 minutes in the second half. Spurs need to attack!
6.16pmIt took Chelsea less than five minutes to break the deadlock after Alderweireld had brought Pedro down just outside the area, picking up an early yellow card for his troubles. Willian subsequently buried his free kick into the far corner on the goalkeeper's side, and Lloris may feel that he should have done better having taken a big step in the other direction before seeing the ball fly past him.
6.18pmSpurs were level before the 20-minute mark, though, and it was Harry Kane who continued his brilliant record in London derbies with a very clever equaliser from Eriksen's cross. Kane stooped at the near post and flicked a fine backward header right into the corner without even looking at wear the goal was, leaving Courtois no chance to keep it out.
6.20pmChelsea ended the first half like they started it, though, scoring again with just two minutes to go until the interval through Willian once again. This time it came from the penalty spot after Moses had gone down under the challenge of Son inside the area. There will be plenty of debate over whether it was a penalty or not, with Moses on his way to ground before the challenge, but it was a stupid decision by Son to go to ground and he couldn't have any complaints at seeing the referee point to the spot.
46 minKICKOFF: Chelsea get us back underway for the second half at Wembley! Just 45 minutes separate them from the FA Cup final as things stand!
48 minIt will be interesting to see how Spurs approach this second half. Chelsea are the team with the greater firepower in reserve on the bench, but it is Spurs who must push for the goal in the coming 45 minutes - will they bide their time or go all guns blazing from the off?
50 minSpurs knock the ball amongst themselves in defence as they look to settle into the game and get things on their own terms. They don't seem to have a great deal of urgency in the opening minutes of the second half here, though.
52 minGOAL! Chelsea 2-2 Tottenham Hotspur (Dele Alli)
52 minChelsea made a quick start to the first half, and Spurs have done the same in this second half to level things up! Dele Alli gets the goal with a really good finish, firing the ball into the top corner at full stretch and on the half-volley. The finish is overshadowed by the pass from Eriksen, though, with the Dane curling a sensational ball around the defence for Alli to convert.
54 minSpurs can smell blood here! They immediately get back on the front foot and Martin Atkinson has a string of decision to make in quick succession as Spurs appeal for a few fouls - including two penalties. On each occasion, though, the referee waves it away.
58 minThis match has certainly lived up to the billing so far. It is England's two best teams, and they are putting on a show today. Great stuff.
59 minLovely footwork from Alli as he takes the ball down well before dipping inside to create space to shoot, but his subsequent effort is scooped a long way off target.
61 minCHELSEA SUBS: Here comes the cavalry! Antonio Conte changes things on the hour mark as Diego Costa and Eden Hazard come on in place of Batshuayi and two-goal hero Willian.
63 minCHANCE! Half a chance for Spurs from a quick counter as Alli looks to return the compliment to Eriksen following their second goal. The Dane is momentarily in space racing down the right flank and Alli manages to pick him out, but Eriksen can't get enough on his header to really trouble Courtois.
65 minThe ball arrives to Wanyama around 25 yards from goal and the Spurs fans inside Wembley urge him to "shooooot!" They may not be doing that next time he gets the ball, though, as he fires his subsequent effort comfortably over the crossbar.
67 minThis match is so finely poised with less than 25 minutes remaining, and we are no closer to knowing who will progress to the final here. We could need extra time and penalties to separate these two!
69 minTOTTENHAM SUB: Spurs make their first change of the afternoon as Walker replaces Son, which will see Trippier switch over to left wing-back.
71 minSpurs win their ninth corner of the match and Chelsea are unable to deal with it initially, but when the ball arrives back into the middle they finally do clear the danger. Spurs on top right now, though!
73 minHere is that goal from Alli, by the way (and more importantly, the pass from Eriksen)...
74 minCHELSEA SUB: A third and final change for Chelsea as Cesc Fabregas replaces Pedro.
75 minGOAL! Chelsea 3-2 Tottenham Hotspur (Eden Hazard)
75 minCometh the hour, cometh the man! Hazard comes off the bench to give Chelsea the lead for a third time today! Walker is only able to clear a corner - Chelsea's first of the day - as far as Hazard on the edge of the area, and the Belgian has far too much time to take a touch and drill his finish into the bottom corner. Spurs have to do it all over again now!
77 minJust 13 minutes remain in this one for Spurs to level things up yet again. As you might expect, it is the Chelsea fans who are in full voice right now!
79 minTOTTENHAM SUB: Spurs make another change here as Wanyama is replaced by Georges-Kevin Nkoudou. Attacking switch from Pochettino!
80 minGOAL! Chelsea 4-2 Tottenham Hotspur (Nemanja Matic)
80 minHow about this for a way to book your place in the final of the FA Cup?! Chelsea surely wrap things up with a stunning strike from Matic, who could not have put that in a better position. Hazard collects a pass from Fabregas before teeing up Matic, who catches his effort as sweetly as he will ever catch one. It flies past a helpless Lloris, smashing in off the woodwork for his first goal of the season. Sensational.
82 minSpurs have shown enough in their last few matches to suggest that they have the goals in their team to still make a game of this in the final 10 minutes, but it is such a big ask for them now. What a match this has been.
84 minCHANCE! Chance for Chelsea to add a fifth as Hazard breaks in behind the defence and skips past Lloris, but he is forced out wide and has to settle for pulling the ball back to Alonso. The full-back tries to apply the finishing touch, but Alderweireld makes an important block.
86 minCHANCE! Another big opening for the Blues! Fabregas lifts a cross into the middle with Costa meets with an unmarked header, but he plants his effort wide of the target when he really should have done better.
88 minIt looks as though Spurs are on their way to a record seventh consecutive FA Cup semi-final defeat, then, but they have more than played their part in an entertaining fixture today.
90 minThere will be four added minutes at the end of this semi-final.
90+2 minYELLOW CARD! Kante picks up a late yellow card for a trip on Alli, giving Spurs a free kick in a good position...
90+3 minCLOSE! How has his one stayed out? Kane drills the free kick towards goal and it squirms under the body of Courtois, but the backspin on the ball somehow sees it stop on the line, allowing the Chelsea keeper to recover and gather.
7.13pmMartin Atkinson brings an end to this thrilling semi-final, and it is Chelsea who book their place in the FA Cup final courtesy of a 4-2 victory over London rivals Spurs. Tottenham showed great fight to twice come from behind, with goals from Kane and Alli cancelling out a brace from Willian. However, Eden Hazard came off the bench to restore Chelsea's lead for a third time with only 15 minutes remaining before Nemanja Matic blasted the Blues into the final with a fourth.
7.15pmThat is all we have time for this evening! Thank you very much for joining Sports Mole for today's FA Cup semi-final as Chelsea beat Tottenham 4-2 at Wembley, and in some style too. I will leave you with our match report, and be sure to stick around for reaction from both camps too. We will have live coverage of the second semi-final on site tomorrow too, so be sure to check back in for that! From me, though, it is goodbye for now!