Swindon boss Richie Wellens was angered by referee Leigh Doughty and his defenders after a 3-1 loss at Peterborough.

Wellens was adamant the Robins should have had a penalty after taking the lead through Jack Payne when Sammie Szmodics appeared to foul Paul Caddis.

Posh then struck back with second-half goals from summer signings Jonson Clarke-Harris (two) and Ryan Broom for their seventh home league win in a row.

Wellens, who was sent off after full-time, said of the referee: “He made a vital mistake at 1-0 up where Paul Caddis is chopped down from behind. It’s a game-changing moment.

“We should be 4-0 up at half-time. We’ve had three one-on-ones and (should have had) a penalty and we were already 1-0 up.

“I’m really frustrated. We got ragged in the last 15-20 minutes. They upped the tempo and closed our centre-backs down a little quicker and three mistakes have cost us.

“Up to 70-75 minutes they’ve not really carved us open. We’ve had five shots on target, they’ve had five shots on target.

“It’s a stonewall penalty on Paul Caddis. I don’t know what the referee sees in that. Paul is probably going to shoot from six or seven yards out or pull it back and he’s just been hacked down from behind.

“If people let me down once I’ll probably give them another chance, but if you keep letting me down then you won’t play.”

Payne slotted home from inside the area on six minutes after Jordan Stevens’ right-wing cutback.

Three minutes after the break Clarke-Harris scored Peterborough’s 4,000th Football League goal when he fired in low from Joe Ward’s cutback.

Siriki Dembele and Clarke-Harris both hit the bar but the striker scored low to his left from the spot on 69 minutes after Szmodics was tripped by Mathieu Baudry.

Broom’s near-post finish 12 minutes from time sealed the points.

Peterborough boss Darren Ferguson said: “Everything we worked on we didn’t do well enough. Our decision-making was poor. We were lucky just to be one goal down at half-time.

“We made two, three really good saves. We had to address that. We changed formation which helped.

“Second-half we were better and scored early which helped. I’m pleased for Clarke-Harris getting his first goal. Then we got a little break with the penalty decision.

“There’s a lot of work we need to do. If teams look at us and think they can play a certain way we have to find better options. We have to be braver or move the ball quicker.

“All the things we seem to do in training we need to do in matches.

“We’re not right there at the moment. I need to find out why. I will speak to the players on Monday. If it’s a confidence thing or not I don’t know. It shouldn’t be, especially at home.”