Good evening and welcome to Sports Mole's live text coverage of the crucial World Cup qualifier between Wales and Republic of Ireland at the Cardiff City Stadium.
Victory for either of these sides tonight would guarantee at least a place in the playoffs and could even be enough to win Group D should leaders Serbia slip up at home to Georgia.
A draw, meanwhile, would ensure that Wales finish above Ireland in the final standings, although the complicated nature of the permutations means that that still may not be enough for a playoff place.
Make sure you don't miss a moment of the action courtesy of our minute-by-minute updates below.
Wales host Republic of Ireland at the Cardiff City Stadium tonight in a match that could see either side win the group, finish second or miss out on the playoffs entirely, so it really is all to play for here.
The exact permutations are very complicated - particularly on the part of Wales - and I will take you through them a little later, but for now let's start with a look at the team news...
Well, no matter how long we have known for, the glaring omission from the Welsh starting lineup is that of Gareth Bale, who remains sidelined with a calf injury which has also left him as a doubt for Real Madrid's Champions League double-header against former club Tottenham Hotspur later this month. Bale's importance to Wales cannot be overstated, but they picked up a good win in Georgia without their talisman on Friday and will be hopeful of doing the same again tonight.
The midfielder scored the only goal of the game in Georgia, and it was some strike too. Aside from being a good goal, it could prove to be a hugely important one too, keeping Wales in control of their own fate heading into tonight's match. Lawrence is rewarded with another start this evening.
Ramsey is the highest goalscorer in the current Wales squad with 13 to his name - the only player to be in double figures for the Dragons from those at Coleman's disposal tonight. Vokes in the next highest with eight goals at international level, although he misses out this evening in favour of Hal Robson-Kanu.
That means an unchanged backline of Davies, Chester, captain Ashley Williams and Gunter, the latter of whom is the most capped player in the current Wales squad with 82. Williams is not far behind, though, and tonight will make his 75th Wales appearance.
Shane Long was also ruled out of the game this morning, which is a big blow for the visitors considering he is the only player in double figures for goals from the current squad. His tally of 17 leads the way since Robbie Keane hung his boots up following an incredible international career.
Murphy has averaged a goal every 55 minutes during the campaign so far, netting three times in 166 minutes for his country - including twice on Friday to fire Ireland past Moldova. Both of those goals came in the opening 20 minutes in Dublin, and both Ireland and Murphy will be hopeful of another quick start this evening.
The midfield pair missed the win over Moldova through suspension, but return to the starting XI this evening alongside Bournemouth's Harry Arter. Hoolahan, Long and O'Dowda are the men to drop out for the visitors.
John O'Shea and Aiden McGeady both have to make do with starting from the bench this evening, despite boasting 219 caps between them, although they could be useful substitutions should Ireland find themselves needing to manage this game.
Wales are currently in the driving seat out of these two teams in Group D, leading Ireland by one point heading into tonight's match. Serbia are a further one point ahead of Wales, meaning that automatic qualification is in their hands this evening as they host Georgia. Serbia will be expected to win that match, but any slip-up would open the door for either Wales or Ireland to win the group and seal their place in next summer's World Cup.
Should Wales win and Serbia draw then Wales would go through as group winners, but should Wales draw then they would need Serbia to lose by two or more goals to ensure they qualify automatically.
This is where it begins to get complicated, though, as even though Wales are likely to finish second with a draw, it still may not be enough to guarantee them a place in the playoffs. There are only eight playoff places available from the nine groups, and Welsh fans will have their eyes peeled on Ukraine's match against Croatia in Group I too as that match will also have an impact on the hopes of tonight's hosts.
A victory for either Ukraine or Croatia coupled with a Wales draw will almost certainly see Chris Coleman's side miss out on a place in the playoffs, while should Croatia and Wales both draw but Croatia score more goals in their draw - such as a 2-2 and a 1-1 - then remarkable it would come down to fair play, which Croatia are currently winning.
For Ireland, things are a lot more simple. Their only choice is to win, which would guarantee them at least a playoff place and could be enough for top spot if Serbia fail to beat Georgia at home - although even a draw for Serbia would leave Ireland needing to win by five goals here.
This is the least likely of the two options, but unless Wales lose tonight then they will not know for certain until tomorrow whether they are definitely out or not. Missing out to either Ukraine or Croatia tonight would leave Wales needing lowly Gibraltar to get something from their trip to Greece tomorrow, and for Bosnia to beat Estonia and overtake Greece as the worst runners-up. A very unlikely scenario.
Wales win: Wales are guaranteed at least a playoff place, and would win the group if Serbia fail to beat Georgia.
Draw: Wales would need a draw between Ukraine and Croatia in Group I, in addition to scoring the same number or more goals than both of those teams, to reach the playoffs.
Ireland win: Ireland leapfrog Wales and finish at least second, guaranteeing a playoff place in the process.
Well, Wales are one of only six remaining teams yet to lose in the whole of the European section of qualifying and come into this match on the back of three straight wins having drawn five in a row before that.
Another victory for Chris Coleman's side tonight would make it four on the bounce for the first time since a run of six under Mike England in 1981.
To put into context what they could achieve tonight - and what they achieved in France last summer - Wales have only ever reached one World Cup before, in 1958, and even that was as a result of some political and footballing irregularities which gave Wales a second chance.
That 1958 team included the likes of Ivor Allchurch, Cliff Jones and the great John Charles, which is the company this latest golden generation - as Coleman has dubbed them - could be keeping with a win tonight.
Wales' unbeaten run at home in competitive matches goes back to September 2013, though, winning six, drawing four and keeping seven clean sheets in their 10 such matches since a 3-0 defeat to Serbia.
That triumph was their first away in a qualifying game without Bale since 2009, when they beat Azerbaijan 2009, and they will need to produce another good performance without their talisman tonight.
Martin O'Neill's side began qualifying so well, with 10 points from the first 12 on offer, but they then took just three points from the next 12 to slip behind Serbia and Wales in the race for a top-two place.
Ireland have won just two of their eight matches across all competitions in 2017, and tonight are looking for consecutive wins for the first time since November of last year. They are, however, unbeaten in their four away games during the current qualifying campaign, winning two and drawing two.
Whatever happens tonight, though, Martin O'Neill will remain in charge for the foreseeable future having last week put pen to paper on a new two-year deal which carries him to the end of Euro 2020.
This is such a tough one to call tonight. The two sides are evenly matched and both missing arguably their best players, while both teams could well need a victory to keep their World Cup hopes alive. It is set up very nicely for the neutral and really could go either way. In usual circumstances with so little to separate the teams I would plump for a draw, but these are far from usual circumstances and there should be a winner this evening simply because both teams need one.
Sports Mole says: Wales 2-1 Ireland
The crucial difference which may lean things in Ireland's favour, however, is that Wales have never beaten their Celtic rivals in a competitive contest. They have twice draw in such circumstances - in 2007 and the reverse fixture of this campaign - but they have also lost twice, with Ireland winning out 1-o winners in another 2007 contest and 3-0 victors in 2011.
The most recent of those came in Dublin in March when they played out a stalemate in the reverse fixture of this one, while they also drew 0-0 in an August 2013 friendly at this very stadium.
Indeed, Wales' recent record against Ireland is poor despite the even nature of the all-time head to head. Ireland are unbeaten in their last seven meetings stretching back to February 1992, while they have only lost one of their last 10.
WALES STARTING XI: Hennessey; Gunter, A Williams, Chester, Davies; Allen, Ledley, Ramsey, King, Lawrence; Robson-Kanu
IRELAND STARTING XI: Randolph; Ward, Clark, Duffy, Christie; Brady, Hendrick, Meyler, Arter; McClean; Murphy
The hosts have controlled the possession so far, but clear chances have been few and far between at either end of the field. Ireland's best chances have come via set pieces, while Wales have largely been limited to long-range efforts.
Aside from that, there has been only a Robson-Kanu header, long-range efforts from Allen and Lawrence and an opening for Davies to speak of for the hosts despite their dominance of possession.
Chris Coleman's biggest concern from that opening 45 minutes will be the loss of Joe Allen, though. The influential midfielder was forced off in the 37th with a head injury after landing heavily following a collision with two Irish players.
We should hopefully have more goalmouth action in the coming 45 minutes, though, as Ireland need a win to stand any chance of qualifying, while a draw may not be enough for Wales either.
Plenty of Welsh fans thought that one had gone in, but Ireland survive!
It stems from Hennessey as he rolls the ball out to Williams, who immediately finds himself under pressure from Hendrick. The Burnley man blocks the clearance, and then takes advantage of some lax defending to burst down the right flank - just about keeping the ball in play.
His delivery from the right goes all the way through to McClean, who plants an unerring first-time finish home.
Incidentally that doesn't change anything for Ireland, who will reach the playoffs with victory regardless of what happens elsewhere.
As things stand their World Cup dream will end tonight and even a draw wouldn't be enough for them to qualify for the playoffs, but should they find two goals in these closing stages then they would actually win Group D and qualify automatically. These are such fine margins!
The visitors were tactically superior to their hosts this evening, keeping Wales at bay and hitting them during the one defensive lapse Coleman's side made. James McClean got the only goal of the game and leads the celebrations, with Ireland now just two matches away from reaching their first World Cup since 2002. For Wales, though, the wait goes on.
Thank you very much for joining Sports Mole for tonight's match as Ireland beat Wales in Cardiff to reach the World Cup playoffs at their hosts' expense. I will leave you with our match report, and be sure to stick around for reaction from both camps too. The final round of European World Cup qualifiers take place tomorrow night, so be sure to check back in for that!
From me, though, it is goodbye for now!