Mikel Arteta could be without the Arsenal striker for three months (Picture: Getty)

William Gallas has fired a warning to Arsenal and Mikel Arteta after Gabriel Jesus’ World Cup injury.

Premier League leaders Arsenal could be without star striker Jesus for up to three months after he injured his right knee during Brazil’s final World Cup group game against Cameroon.

The Gunners confirmed earlier this week that Jesus underwent successful surgery on his knee but did not provide a timeframe for his return to the team.

Arsenal surged five points clear of defending champions Manchester City before the World Cup started, as the north London side seek a first league title since 2004.

But Jesus’ injury setback could derail Arsenal’s title challenge, with former Gunners defender Gallas claiming Arteta’s side are now ‘in trouble’.

While Jesus has not been prolific in front of goal this season – scoring five goals in all competitions since his £50m move from Man City last summer – he has been praised for his all-round play, with Arteta insisting he has taken the team to ‘another level’.

‘I said before the World Cup that Arsenal need another strong striker because if Gabriel Jesus gets injured then they’ll be in trouble,’ Gallas told Genting Casino.

William Gallas says his former club are ‘in trouble’ (Picture: Getty)

‘He’s a very important player in their system so for me, they are in trouble now.

‘I hope those in charge of recruitment know who they want to buy because they’re in a good position to win the title and I hope they’re already sure who they’re going to buy in January.’

Jesus, meanwhile, has vowed to ‘come back stronger’ after a knee injury ruled him out of the remainder of Brazil’s World Cup campaign.

Following his operation, Jesus posted a picture from his hospital bed along with a message which read: ‘God is wonderful, I will be back stronger.’

Arsenal midfielder Granit Xhaka has also addresses Jesus’ injury blow, saying: ‘I spoke with him straight after the Cameroon game. We have contact with each other, with all the players we have here in the World Cup.

‘It’s a shame because you saw in the first round of the Premier League how important he is for us. I don’t know how big the injury is, maybe two or three months, I think. But he is a strong guy.

‘It’s a small injury for him I think, and we will support him. He knows that we are behind him and hopefully we can get him back as quick as possible.’

MORE : Ian Wright slams Graeme Souness for comments on former Arsenal striker Olivier Giroud

MORE : Granit Xhaka backs Arsenal star to replace Gabriel Jesus after World Cup injury

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