Lisandro Martinez produced a defensive masterclass for Manchester United against West Ham on Sunday.

The Argentine defended for his life to help Erik ten Hag's side keep a clean sheet during their 1-0 victory.

The former Ajax defender was widely criticised following his £56.7 million in the summer.

It was certainly a difficult start to life at Manchester United, following defeats to Brighton and Brentford in the opening two matches. Martinez was substituted at half time against Brentford with United 4-0 down.

It led to Sky Sports pundit, Jamie Carragher, insisting that the 5ft 9in 'can't work' playing at centre back for Manchester United.

"Now, we should never judge managers or players too early, but I'm convinced this can't work because the size of him playing in a back four," Carragher said.

"Maybe he could go left-back, maybe he could play in a back three, but in a back four, he cannot play there in the Premier League."

A penny for Carragher's thoughts right now because Martinez has transformed his fortunes.

During the win against West Ham Carragher's Sky Sports colleague, Gary Neville, insisted that Martinez has been "Man Utd's best player by a mile."

READ MORE: Lisandro Martinez's incredible highlights vs West Ham

Chants of 'Argentina, Argentina' could be heard echoing around Old Trafford during the 90 minutes due to his performance.

But it's not just Martinez's displays that has seen him become a fan favourite.

His passion is something that the club have been crying out for. And that passion was clear for all to see when the final whistle blew against West Ham.

Footage that focuses solely on Martinez at full time has emerged.

It shows him desperately trying to defend a corner but celebrating wildly.

On the final whistle, he jumps in the air in delight, appears to bump into Tomas Soucek, jumps onto David de Gea's back, hugs Diogo Dalot, fist pumps the crowd, pushes Marcus Rashford before sharing a lovely embrace with Harry Maguire.

VIDEO: Lisandro Martinez's reaction at the final whistle vs West Ham

https://twitter.com/UtdPlug/status/1587036221934604288

Manchester United fans were loving it. Check out the best reaction:

Man Utd fans react to Martinez's passion at full time

Man Utd fans react to Martinez at full time
Man Utd fans react to Martinez at full time
Man Utd fans react to Martinez at full time
Man Utd fans react to Martinez at full time
Man Utd fans react to Martinez at full time
Man Utd fans react to Martinez at full time

Souness still has doubts about Martinez

Despite his recent performances, Graham Souness claimed that he still has some reservations about the defender.

"That worry for me is still there," Souness said on talkSPORT on Monday. "If you watch at set-pieces, he still uses a blocker or they use him on the near post. He's not got the physique to take on the big guys and man-mark them.

"I think he's brought a bit of aggression to them. He definitely has. My experience in the dressing rooms are, if you've got a couple people that are willing to stand up and fight, you've got several people coming in behind you.

"There's a lot to like about him. I like his aggression. The first thing he did, when he played Liverpool, he's gone right through Mo Salah early on. For the rest of the game, Salah was looking for him. I like that.

"I just feel, when you're that size, you'll get caught. You'll get pinned in the box. I don't think he's terribly quick. I don't think he's terribly good on the ball. But he's got something about him that makes other people play [well].

"5ft 9in and he's playing against guys that are 6ft 2in. I can't tell you a centre-back, in my time in the English game, that's been super successful being that size."

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