'I'm sure he will skyrocket': John Mousinho's stark challenge to Portsmouth underachiever and ex-Cardiff City and Oxford United man

The Irishman will be handed his second start in 10 matches in the Bristol Street Motors Trophy trip to Leyton Orient (7pm).

With Tino Anjorin expected to be sidelined for up to eight weeks after tearing his hamstring and Anthony Scully still in the treatment room, it offers a prized opportunity to push his credentials for a regular spot.

By Mousinho’s own admission, his former Oxford United team-mate has failed to live up to his potential since arriving at Fratton Park in July.

Yet he remains convinced the 27-year-old will soon turn ‘glimpses’ of form into devastating results.

Mousinho told The News: ‘With Tino’s injury, there might be an opportunity for Gav and he must find it in himself to show why we brought him to the football club.

‘We have glimpsed it throughout his short spell at Pompey so far. Leyton Orient offers the chance to build him back in and get him going again, we know what he’s capable of and, once he does, he will be a brilliant player for us.

‘At Leyton Orient in August was his best game for us and he’s been part of the team which have built themselves up to the top of the table.

‘The biggest compliment we can pay is we thought he was doing something right, but still know there’s a huge amount of potential in there, otherwise there’d be no point bringing him to the football club,

‘What we need him to do is put all those glimpses together and start churning out those consistent performances.

‘You can’t compare players exactly, but there are some useful comparisons as well. It’s never quite straightforward and it took Paddy Lane quite a while, having suffered for the opening six months of the season at Fleetwood.

‘Gav’s probably had a longer period of frustration, it was two or three years in and out of Cardiff, while he played a few games here and there for Northern Ireland.

‘We know he’s going to get there at some point, the sooner the better, but it takes a bit of patience. We have to make sure we work through all of that and probably harness the potential.

‘Once he gets his first goal for the club, I’m pretty sure things are going to skyrocket.’

Whyte was introduced in the 44th minute for the injured Anjorin in Sunday’s FA Cup defeat at Chesterfield.

Yet, like the vast majority of his playing colleagues, he struggled as the Blues failed to break down Paul Cook’s non-leaguers amid an awful team display.

Mousinho added: ‘You see the glimpses. There were a couple of times in the first half where Gav turned really well and got himself into some nice positions.

‘We just want to see him progress from there, be more positive, make sure he gets the ball forward, make sure he attacks with purpose.

‘We’re not asking him to do anything he isn’t capable of doing.’