The Cod Army looked set to record their second win of the new season following Callum Camps’ 55th-minute opener.
However, Jack Taylor and then Sammie Szmodics came to the Posh’s rescue on 91 and 95 minutes respectively to ensure the hosts picked up their first victory of the 2020-21 campaign.
That left Barton fuming at the final whistle, with the match official on the receiving end of his wrath.
He told the Fleetwood Weekley News: ‘I’m clearly disappointed because at 90 minutes the game was over.
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‘We controlled the game and seemed to be going back to Highbury with three well-deserved points. But the referee, from our point of view, had a really poor afternoon.
‘I don’t think he ever had control of the game. Frankie Kent (Peterborough defender) elbowed Sam Stubbs across the face, but whether it was meant or not the referee should have consulted his linesman.
‘We’ve seen two more elbows on Ched (Evans) but no action was taken. The challenge on him by (Nathan) Thompson was a red card.
‘I’ve watched it back and, yes, the referee is on the wrong side of it but the fourth official is there to help him.
‘We played them off the park but those challenges make it dangerous for my players. From our regard, I’m disgusted with some of the challenges that were made.’
Peterborough manager Darren Ferguson praised his side for their never-say-die attitude.
He told the Peterborough Telegraph: ‘We have not had that feeling for a while, coming back from 1-0 down and winning it.
‘It was fantastic from my players, who just kept going.
‘For the last 25 minutes we just kept plugging away and fortunately came up with two really good finishes for the goals.’
Oxford manager Karl Robinson had no doubt who was to blame for his side’s 2-0 defeat at the hands of Sunderland – his players.
The U’s, who beat Pompey in the League One play-offs last season remain without a point this term, following their opening-day loss against Lincoln.
They recorded defeat number two at home to the Black Cats yesterday, with the visitors scoring through Luke O’Nien (47) and Lynden Gooch (82).
As a result, Robinson planned to have his players report for extra training today as a punishment,
He said: ‘Some of the stuff in that period was atrocious.
‘That’s as bad a performance in the second half as I’ve seen.
‘I know what I want to say, but equally I’ve got to be very careful with what I do say for the benefit of the players who are in the club right now.
‘We’ll be in tomorrow morning (Sunday), very early, and we’ll be going through that game.’
Hull boss Grant McCann said his side had to dig deep against Crewe to ensure they maintained their winning start to the new season.
The recently-relegated Tigers beat the newly-promoted Railwaymen to sit joint-top of the table alongside Ipswich and Lincoln.
Mailk Wilks scored the all-important winner in the 81st minute, ensuring a good week at the KCOM Stadium.
McCann told the Hull website: ‘It was a bit scrappy.
‘We probably weren’t as good as we have been in the last couple of games but we dug deep to get the goal.
‘It’s three wins in a week, with two clean sheets in the first two league games and we should had another one at Leeds.
‘We were playing against a very good team and I have to give credit to Crewe. They’re used to winning and they play a certain style that’ll cause people a lot of problems.
‘But we stuck to our task defensively. Yes, we can be better going forward but we still created some half decent chances in the first half where we could have been more clinical. But we dug deep in the second half to get the job done which was pleasing.’
Lee Bowyer fears complacency may now be at the root of Charlton’s problems after they lost 3-1 at home to Doncaster Rovers.
The Addicks welcomed 1,000 fans back into the Valley as they took part in the EFL’s latest test event for supporters.
However, there was little to cheer for the home fans as Rovers’ ran out comfortable winners.
Charlton have problems off the field due to the ownership crisis at the club.
Now Bowyer, who is unable to add to his squad because of those issues, fears complacency may already be setting in.
‘I just said to the players, I hope things change quickly because we need players, Bowyer told Londonnewsonline.co.uk.
‘This group that’s there now, there isn’t any competition to make them realise that you’re not going to be playing next week if you don’t do well.
‘As it stands today, there’s not that competition.
‘This group think they’ve played bad and that’s OK, we’ve got another game next week, don’t worry.
‘You ain’t going nowhere if you’ve got a squad like that. I just told them that. We need to get some bodies.’