Mikel Arteta has said he and Arsenal must find a way to cope without Bukayo Saka after confirming the England forward is set to be sidelined for “many weeks” due to the hamstring injury he sustained against Crystal Palace on Saturday.

Saka was pictured leaving Selhurst Park on crutches after he limped off during the first half of his side’s 5-1 victory, with Arteta confirming on Monday that the 23-year-old has torn a hamstring. The Arsenal manager described it as a huge blow and also revealed that back-up Raheem Sterling is likely to be out for several weeks after picking up a knee injury in training.

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Asked how he plans to replace Saka – who has scored nine goals and provided 13 assists this season in all competitions – Arteta admitted he has yet to formulate a plan but is hoping that existing players at the club can help to fill the void, rather than having to sign reinforcements in January. It is possible – likely, even – that Gabriel Martinelli will play on the right of Arsenal’s attack instead, with Leandro Trossard taking his place on the left.

“I’m putting some ideas together. I haven’t got there yet but I have a few,” Arteta said. “I want to speak with them as well to understand how we are going to generate that and take it in a positive way. It means we’re going to be different.

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“We went through the period with Martin [Ødegaard, being injured] and the period with five, six defenders missing. We’re looking at it with positive energy.”

It is the third time this season that Saka has suffered a hamstring injury. He withdrew from England’s squad after a Nations League game in October and was substituted against Chelsea in November after complaining of discomfort which forced him out of the next England squad. Saka has missed only seven Premier League matches in the past three-and-a-half seasons and Arteta believes that an excessive workload over that period has contributed to his injury.

“It’s probably the accumulation of all the seasons,” he said. “For example, Bukayo and Declan [Rice] played over 130 games [each] in the past two seasons, so what’s going to happen in the third one and the fourth one if that continues in that way? Probably it’s unsustainable. Unless we find ways to physically turn them into monsters who can cope with anything.

“The fact that you train and recover, that’s not a good pattern because the body needs to train, the muscle needs to train. If you just play and recover you start to lose a lot of factors in your body that are key to physical performance. Not just to play not to get injured, but to become a better athlete which is very different and keep evolving as an athlete. That’s a challenge, but OK we’re going to do it.”

Asked whether he can see any prospect of the schedule changing given the expanded Champions League format and introduction of the Club World Cup next summer, Arteta seemed sceptical. “I hope they [the authorities] are listening,” he said. “Whoever is in charge, can they actually do something right now with the commitments that are already in place over the next three or four seasons? Very challenging, very difficult I think.”

Arteta also said Saka was “gutted” after picking up the first major injury of his career. “You can tell that he has not been injured [before] because he was really, really emotional and really down. And we need to lift him up,” he said. “It is a big part of his job. And he will be fine but he is going to need a few days.

“He will immediately realise that he is so important in that dressing room. His energy level, his body language, and how he communicates with the rest of the team has to be really good because it is the only way at the moment he can help, so he better do that well.”