Frank Lampard insists his Derby team will go to Southampton believing they can cause an FA Cup upset.
The Rams have already beaten Premier League opposition away from home this season, knocking out Manchester United in the Carabao Cup in September.
Lampard's side produced an impressive comeback in the original tie 10 days ago against Saints, with goals from Jack Marriott and Tom Lawrence wiping out a two-goal deficit to earn Derby a 2-2 draw and a replay.
"You have to believe when you go to those places, if not you are half beaten before you start," said the Rams boss.
"So the no-fear factor is us going and believing in what we are doing, believing individually and collectively. We have talent and we have desire to win the game. We have shown we can match anybody.
"We love the FA Cup and it is another opportunity for us to show that we have players with the ability to match the Premier League teams."
Lampard recalled that night at Old Trafford towards the beginning of the season, where Derby came from behind to lead 2-1 and were only denied a famous victory by Marouane Fellaini's equalising goal deep into injury time. The Rams then won the subsequent penalty shootout.
He wants his team to reproduce that kind of performance at St Mary's on Wednesday night.
"We had energy, aggression, quality, we showed the complete package on that night as far as we are concerned," said Lampard.
"Every game throws up different issues but you have to have a template and a benchmark and the Manchester United game would fall into that. We are striving for that excellence and we must always do that.
"It will be a tough game without a doubt, no matter what team they put out. Going to a Premier League stadium, there are going to be lots of challenges for us but ones we should be up for and one's we already know we can handle.
"I want to get through to the fourth round. I will pick a team that I believe will go there and win the game. With the strength of the squad here, there may be some changes, but I believe it will be a team that can compete."
Harry Wilson will be back in contention for the Rams. The 21-year-old attacking midfielder, on-loan from Liverpool, has missed the last two games due to a hip problem, including the first game against Southampton.
The winner on Wednesday night will travel to League One Accrington in the next round later this month.
