Arsenal are likely to be without midfielder Alex Oxlade-Chamberlain when they host West Ham United on Saturday and could be missing the England midfielder for several weeks. Oxlade-Chamberlain suffered a hamstring injury that forced him off early in the second half of Arsenal’s 2-1 victory over Manchester United in the FA Cup quarterfinals on Monday. Speaking on Wednesday, manager Arsene Wenger explained that the extent of the issue would soon be revealed.

“Chamberlain has a hamstring strain, the only thing we don't know is how bad it is because usually the scans are only done 48 hours after the accident,” he said, according to Arsenal’s official website. “That will be done today.”

The latest problem will be of particular frustration to both player and club, with it being the fifth spell on the sidelines he has been forced to endure because of injury this season. At Old Trafford, the 21-year-old was playing just his third game since returning from a groin injury suffered in January.

If Oxlade-Chamberlain is now ruled out for a matter of weeks rather than days then he will miss next Tuesday’s crucial Champions League second leg against Monaco, in which Arsenal trail 3-1 from the first match at the Emirates Stadium. He could also be absent for the Premier League match with Newcastle United on Mar. 21, but Wenger would be looking to have him back following the international break for Arsenal’s encounter against Champions League rivals Liverpool at the start of April. However, Oxlade-Chamberlain must be considered a doubt for England’s Euro 2016 qualifier against Lithuania on Mar. 27.

Almost certain not to be involved for England in that match is fellow Arsenal midfielder Jack Wilshere. The 23-year-old has not played since November when he was forced to undergo surgery on an ankle injury. Last month he returned to training, but then underwent another procedure that Wenger described at the time as “minor.” Yet his return date remains unclear.

“Jack is progressing well. He is not back in training yet,” Wenger said.

There is better news regarding Mathieu Flamini. The French midfielder has been absent for close to a month due to a hamstring complaint but Wenger revealed that “he could be available for the squad on Saturday.”

January signing Gabriel will have to wait a bit longer for his return from a minor hamstring injury suffered against Queens Park Rangers 10 days ago. He is due to return to training early next week, which could give the Brazilian center-back an outside chance of being involved in Monaco. Yet, while that match looms large on the horizon, Wenger has insisted that it will not be in his mind when he makes his team selection for the clash with West Ham.

“We were at a high level of fatigue because we played against Monaco, Everton, QPR, Manchester United, all very physical games,” he said. “I will have to test medically, physically, how the players are on Friday, and I will make my decision then. The big priority is of course West Ham.”