Peterborough boss Darren Ferguson called his players ‘bottlers’ after they lost a Carabao Cup penalty shoot-out 3-1 at League Two Mansfield.
Posh came from behind to lead but the game ended 2-2 when Lucas Akins netted a stoppage-time penalty.
Former Peterborough goalkeeper Christy Pym then saved two spot-kicks before Davis Keillor-Dunn netted the winner as the Nottinghamshire team ensured they remain the only EFL side unbeaten this season, making the fourth round of the competition for the first time since 1975 .
Ferguson said: “I don’t like criticising my players in public and I very rarely do as a manager. But I am not letting them get away with that one. They absolutely bottled it.
“For the first 65-70 minutes, the penalty aside, I thought we were really, really good and they couldn’t get near us.
“But all of a sudden Mansfield started going back to front a bit more and we just bottled it, pure and simple. I can’t dress this one up.
“It is terrible result, there is no other way of putting it, and it is a massive opportunity missed.
“It was a massive chance to get in the last 16 and I hope Mansfield now get Manchester United away or something like that so our players can see it tomorrow night.”
Will Swan put the Stags ahead from the penalty spot in the fifth minute but the visitors piled on the pressure and levelled when Jonson Clarke-Harris’ 25-yard free-kick went through the wall and past Pym on the half hour.
Clarke-Harris swept home a second in the 47th minute but Mansfield raised their game and began to dominate and were rewarded with Akins’ spot-kick success three minutes into added time, before emulating their shoot-out win at Sheffield Wednesday in the previous round.
Delighted Stags boss Nigel Clough said: “We are into the next round for the first time in nearly 50 years, which is a hell of an achievement, but so is going 12 games unbeaten.
“For quite long spells we were second best as they were so good. There wasn’t too much we were doing wrong. They were just very competent.
“The respect they showed us by naming a full side said everything. They are a top side in League One and you can see the big difference, the pace and the speed they move the ball.
“We just hung on in there, trying not to concede a third goal and at 2-1 anything can happen in the last 20 minutes.
“I thought the equaliser was coming after Lucas Akins’ goal that was offside. It was no more than we deserved for hanging on in there.
“We have been good taking penalties in training and at Sheffield Wednesday so we saw no reason why we couldn’t win the shoot-out.”