Arsene Wenger has suggested that a recent injury sustained by influential Arsenal centre-back Laurent Koscielny is serious, although the club are yet to establish the extent of the damage or determine how much time he could stand to miss.

Koscielny started alongside regular defensive partner Shkodran Mustafi against Manchester City on Sunday (2 April), but was withdrawn at half-time of a 2-2 Premier League draw at the Emirates Stadium after sustaining an Achilles problem. While the French international will definitely be absent for tomorrow night's visit of West Ham United, an accurate time frame for recovery can only be successfully established once he has undergone a scan.

With that not due to happen until later on today, Wenger is yet to rule the player out of next week's trip to Crystal Palace. However, it could be that this is an issue that will sideline him for the remainder of the campaign.

"It is serious," underfire Wenger was quoted as saying of Koscielny's injury by the BBC at his pre-West Ham press conference.

"If he has ruptured the fibres then he could be out for a few weeks, if not, he could be available to face Crystal Palace. I will tell you more tomorrow."

Sixth-place Arsenal could welcome back Aaron Ramsey and Alex Oxlade-Chamberlain for that aforementioned clash with London rivals West Ham after both players were omitted from the squad to face City due to injury.

Ramsey has been suffering from a recurring calf problem, while his fellow midfielder was ruled out with another hamstring issue. The duo will be further assessed today, although Wenger is hopeful that they will each be passed fit.

Laurent Koscielny
Laurent Koscielny is set to undergo a scan on an Achilles injury picked up against Manchester City Reuters/John Sibley

"Chamberlain and Ramsey have a test today," he said. "There is a good chance they are back in the squad."

Petr Cech is not in contention for West Ham, although could return for next Monday's trip to Selhurst Park after being forced off during the first half of last month's 3-1 defeat at West Bromwich Albion with a calf injury. With Koscielny in the treatment room, Per Mertesacker could take his place in the matchday 18 for only the third time since recovering from a long-term knee injury suffered during preseason. He has yet to make a single first-team appearance in 2016-17.

"Per Mertesacker is available to play," Wenger added. "He could be in the squad for tomorrow. Cech is not available tomorrow. Maybe Monday."

Out-of-favour forward Lucas Perez is not expected to play any part against the club with whom he has been linked with a £17m ($21.1m) summer move due to a thigh complaint. Long-term absentee Santi Cazorla, meanwhile, has been lost for the season after persistent ankle and Achilles trouble.