He was, however, magnanimous enough in defeat to deliver plenty of plaudits for Darren Ferguson’s relegation battlers after their second-half turnaround earned a vital victory.
Rowett was particularly impressed by the performance of Siriki Dembele for Posh and also admitted his side were guilty of failing to deal effectively with Jonson Clarke-Harris following the match-winner’s introduction from the bench.
He said: “It was another hugely disappointing afternoon for us.
“We played so well against Bournemouth to then not perform when we lost to Hull.
“We then bounced back and did so well to beat Birmingham but then didn’t back it up again here.
“Peterborough were thoroughly deserving of their victory and played really, really well.
“They were aggressive and brave in terms of the way they did things and we just fell short again.
“We worked a lot on being good out of possession to allow us to go and counter-attack – and we scored a very good goal doing that.
“We were ahead at half-time away from home despite not playing anywhere near as well as we can.
“We changed formation in the second half as we felt Peterborough were getting into our defensive third too easily, but it was the same story of not defending well enough.
“We just kept making foul after foul after foul which allowed Peterborough to keep putting free-kicks into our box.
“We couldn’t deal with Dembele who was excellent and wriggled out of every single situation he found himself in.
“We conceded two goals from absolutely basic errors and you’re not going to win games when that happens.
“Clarke-Harris ended up through on goal all alone behind our back four for the first goal which is not acceptable. Then he ended up completely free on the back post to score from a cross for the second one.
“We didn’t get any free chances anywhere on the pitch but we gave them two for goals.
“Peterborough’s movement around us was bright and we struggled to deal with it.
“When we had the ball we didn’t use it well enough. Our only hope was to defend properly and we didn’t do that either.
“We were sat in eighth before the game and we had a fabulous opportunity to show what we’re all about, but all we did was put another tepid performance in to stop us getting into the higher part of the league.”