Portsmouth manager John Mousinho condemned a fan entering the field of play in protest against the awarding of a late penalty that secured his team a 1-0 win at Port Vale.

The home supporters were absolutely incensed as they felt they had a strong claim for a free-kick on Ethan Chislett, moments before Conor Grant brought down Abu Kamara in the box.

Referee Craig Hicks pointed to the spot, though, and leading marksman Colby Bishop converted in the 88th minute to keep Pompey top of the League One table.

A couple of minutes later after play had re-started, the fan entered the pitch and attempted to confront Hicks from behind.

Having seen the fan closing in on him, Hicks ran away before stewards stepped in and dealt with the situation.

“First of all we don’t want to see any of that on a football pitch,” Mousinho said.

“It was a really bizarre incident.

“Thankfully nothing happened and the referee managed to evade the fan. Just very, very strange.

“But I think for the boys to compose themselves after that – there’s some really young lads out on the pitch as well – and make sure they then dealt with the barrage after that for six or seven minutes, that’s how you win games I think at any level, but particularly at this level.

“If you go 1-0 up late away from home, you’re going to have to sustain attacks and corners and crosses, and we did that really well.”

Port Vale released a statement shortly after the conclusion of the match, condemning the actions of the individual.

“We will work with the relevant authorities to ensure the matter and the individual is dealt with a zero tolerance approach,” it read.

“We remind all supporters that entering the field of play is a criminal offence.”

Valiants boss Andy Crosby believes the initial challenge on Chislett was by no means a definite foul.

“I think the initial challenge with Chis and their player, having looked at it now, I think it could have gone either way – I’ve got to be honest,” he said.

“The referee had a decent view of it.

“Sometimes you get them, sometimes you don’t.

“And then obviously the ball breaks into the box and taking that incident in isolation, I think then it’s a penalty yeah.

“We’ve got a set of players who are representing the club and care about it.

“We don’t want to lose games of football obviously, so when you concede a goal in that manner late in the game against the league leaders, obviously it’s frustrating and people are angry.

“But we have to look at that and learn lessons from that game like we do every one, and focus on the next one.”