The Belgian youngster struggled during his 45 minutes on the pitch (Pictures: ITV / Getty)

Roy Keane and Ian Wright have both criticised Albert Sambi Lokonga’s performance in Arsenal’s FA Cup defeat to Manchester City, with the former branding his display a ‘big concern’.

The Gunners were equal to their opponents in the first half of Friday’s fourth-round tie but gave a meeker performance in the second half, mustering just one shot on goal as Nathan Ake’s tidy finish secured a 1-0 win for the hosts.

Lokonga was introduced at the break in place of Thomas Partey – who injured his rib and will undergo a scan – and both Keane and Wright felt he struggled and left far too much space.

Speaking on ITV Sport after the match, Wright said: ‘It did seem like [Julian] Alvarez, when you see him there, who’s picking him up?

‘Obviously any striker worth his salt is going to turn and shoot. I think Jack Grealish’s vision and capability, keeping the ball and then noticing Ake.

‘But look at the amount of space [Alvarez] is in. Someone has got to be there, whether it’s [Fabio] Vieira or it’s Lokonga. Someone has got to be closer, too much space.’

Focusing on Lokonga, Wright continued: ‘With someone like Sambi, he needs minutes, he needs to be playing, he needs to be able to understand and be more wary of where he is and what he needs to do and where he needs to be dropping in.

Lokonga has only started two league matches this season (Picture: Getty)

‘You’ve got to kind of sense that danger and that’s why he needs the minutes in games of this quality, because that’s where you learn.’

Keane, though, was not in the mood to excuse Lokonga’s lacklustre display, interjecting: ‘But you hope at this stage and at this level they’ve already learned that part of the game. It’s a big concern.’

Picking apart the goal, the Irishman continued: ‘Too easy. Obviously you’ve got some defenders back there – brilliant awareness obviously from Jack and it’s like a striker’s finish [from Ake] – but for the initial ball into Alvarez I think Arsenal lost their shape for 10 or 15 minutes with some of the changes.

‘It’s a brilliant strike almost into the side netting, but just before that almost a lapse, they [Arsenal] were almost just having a breather at the wrong time.

‘It’s a bit of a lack of communication from your centre-halves to your midfielders, they just kind of switched off for five or 10 minutes around that time.’

Wright was also disappointed with Arsenal’s lack of bite in the second half, saying: ‘We didn’t quite get at them enough, we didn’t quite get the ball in that midfield area and get Saka going. Obviously Saka went off, Martinelli came on for Trossard – I thought he did pretty well.

‘But I didn’t think we threatened them enough. When they scored we seemed to get a little bit more of the ball, but they [City] seemed in control of what we were doing, we didn’t threaten as much as I thought we could have.’

MORE : Thomas Partey set for scan on rib injury after Arsenal defeat to Manchester City

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The pundits felt he was at fault for Nathan Ake’s goal.