Ex Arsenal player Jack Wilshere will miss up to six weeks following surgery on an ankle injury.
Wilshere sustained a sprained ankle in training last week and the problem was so serious that an operation was required.
Wilshere left Arsenal on a free transfer after discovering he would not be a regular starter at the London Stadium.
West Ham’s head of medical Richard Collinge confirmed the operation had been successful. In a statement on the club’s website, Collinge said: “Jack underwent successful surgery in London on Monday morning. The surgeon was happy with the procedure and all went as planned.
“We envisage he will only need a relatively short period of rest and will then start his rehabilitation. Jack is focused and determined to get back training as soon as possible.”