The Blues were three goals ahead and looked to be comfortably progressing against their Sky Bet League Two opponents before Sullay Kaikai came off the bench and score twice to get the score back to 3-2.

It was the Championship side who progressed though after their third away victory of the season.

“All of a sudden you’ve got a right old finish on your hands, but it doesn’t matter. What matters is winning,” Davies said.

“We’ve had plenty of games this season where we’ve deserved so much more. Today we’ve deserved to win, absolutely, and we did, and we’re through to the next round.

“Today was all about can we win after winning, and build that momentum. Today was about continuing that and that winning feeling.

“We got ourselves into a great position, then had a bit of an unnecessary stressful finish, but that’s the FA Cup for you.”

Forward Kyogo Furuhashi ended a 23-game run without a goal by netting Birmingham’s second, and Davies assessed his performance.

“I thought he was really good tonight. The second goal was all about Kyogo. He makes it all himself, chases a lost cause and takes his goal well,” Davies added.

“You can see the reaction from all the players, himself, the fans, the staff. Everyone will be really chuffed for him and it meant a lot to him.”

Neil Harris wanted the use this season’s cup runs to spur Cambridge on to a successful end to their League Two campaign.

“If I want to grow this football club then come on, let’s win those games. Why can’t we? Why can’t we drive forward and cause upsets?” Harris said.

“What I will say is that cup competitions this year have been really good for us. We’ve had three great games in this. We go out in a fashion of real pride, appetite and aggression in the way we’ve played at times. A pat on the back for the lads, but that’s now done.

“We’re out now, now it’s just 22 league games to go. They’re huge games for us. We’ve got ourselves into a brilliant position in the league by sheer determination and hard work.

“Keep pushing, keep developing the group with and without the ball, add in the transfer window and we’ve got 22 huge games in front of us.”