AFC Wimbledon midfielder Peter Sweeney has backed butterfingers keeper Seb Brown to bounce back after his mistake helped Coventry City send the Dons crashing out of the FA Cup.

Brown was dramatically thrust into the starting line-up on Friday night after first-choice shot-stopper Ross Worner was held up in traffic due to an accident on the A3.

He had been out of the side for almost a year following a number of high-profile errors led to him being dropped between the sticks and loaned out to Woking last season.

Worner’s absence presented the Wimbledon fan with a chance to redeem himself but instead his fairytale cup return turned into a nightmare at Kingsmeadow.

Things were going to plan for the home side as they deservedly took the lead in the second-half through on-loan Charlton striker Michael Smith’s header.

But Brown then spilled a routine cross which allowed Callum Wilson to level the score, setting up a 3-1 Sky Blues turnaround that dumped Neal Ardley’s side out of the competition.

Opener: Michael Smith gave AFC Wimbledon the lead against Coventry

Ardley admitted in the aftermath that it would be difficult for his backup keeper to recover from the setback despite putting an arm round the ex-Brentford youngster in the dressing room.

Sweeney says Brown was consoled by all of his team-mates and is hopeful the 23-year-old has the mental toughness to put the incident behind him.

“Mistakes happen every day in training, every game, it’s just one of those things,” he said.

“Seb’s a good keeper and he can’t let that affect him. It could’ve happened to anyone. There was probably 500 mistakes on that pitch. It’s just one of them things and we’re all gutted about it, but we’ve got to take the positives out of that game.

“It’s another massive game on Saturday against Portsmouth. You can the focus we’ve had in the two games so we will prepare all week and try and get the right result.”

Late: Ross Worner

Worner arrived on the final whistle last week after getting stuck in a seven-mile, five-hour, queue on his way to the cup tie from Surrey.

It was a first for Sweeney, although the former Millwall midfielder admits he was cutting it fine too as a number for the Dons players almost suffered a similar fate.

“I’ve not seen it happen before,” Sweeney said of Worner’s late arrival.

“I was pretty late myself, some of the others boys were as well, it was a nightmare. Seb trains hard though and prepares himself well so it was no problem for him to step in.”