Fitzsimons: Referee 'killed the game' after 'crumbling' under derby pressure

There was no intent or malice behind Perkins’ challenge on Peter Kioso, and neither was there much force, but the height of the tackle prompted Busby to send the wing-back for an extremely early bath.

That meant the odds were stacked against Cobblers and they duly succumbed to defeat despite a spirited and gutsy effort with 10 men for more than 80 minutes.

"It’s a derby and it’s going to be feisty and we were 10 minutes into the game,” said Fitzsimons. “Yes, his boot is high but is it high enough for a red card? I don’t think so. The crowd have got up and got on his back and he’s crumbled a little bit to be honest.

"He’s killed the game off because for 80 minutes we’re playing with 10 men and we’re obviously up against it. The game’s dead. Unfortunately we can’t rely on the officials but I thought we did excellently to stay in there and to keep fighting.”

Perkins, who only recently turned 22, is in his first season at professional level. "It’s one of those things for Jack,” added Fitzsimons. “He’s been excellent all season and it’s a learning curve.

"He’s not gone in maliciously and he’s not gone in with any force, you can see that straightaway. Maybe he could have a little bit more nous but he’s a young lad and he’ll pick that up. He’ll learn and when he comes into another derby in the future, he’ll understand next time.”

Harry Leonard scored just before and just after half-time for Posh but Tom Eaves pulled one back and Cobblers nearly snatched an unlikely draw.

Fitzsimons continued: "It was a tough afternoon with Perks getting sent off so early but we stuck in there really well and had a couple of chances. It just didn't fall for us.

"They looked like they were going to be fair and we were piling on the pressure quite heavily. They were shot to bits, which is testament to us and the lads and the staff because it was a good performance all-round despite the sending off.”