West Ham right-back Vladimir Coufal is set for a spell on the sidelines after the club confirmed he has undergone surgery on a groin injury.
The defender, who has been managing the problem for a while, missed last weekend's 1-1 draw with Newcastle due to an issue with his hernia, with Ryan Fredericks taking his place.
In a statement released on Thursday, West Ham confirmed Coufal will now be unavailable to David Moyes while he undergoes rehabilitation.
"West Ham United can confirm that Vladimir Coufal has had successful surgery on a groin injury," the club said.
"The 29-year-old defender has been troubled by an ongoing problem and, following specialist consultation, underwent an operation in London on Thursday morning.
"Everyone at West Ham United would like to wish Vladimir a full and speedy recovery."
Head of Medical Richard Collinge added: “Vladimir’s surgery went exactly as planned and he will begin his rehabilitation at Rush Green immediately.”
It's unknown how long Coufal will be out for, although the defender's absence will be a big loss to Moyes as his side look to pick up vital points in the hunt for a Champions League place.
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Johnson could now be set for another run in the starting XI after coming on at the break against Newcastle United.
Coufal had not been in the best of form and Fredericks failed to take his chance during the draw with Newcastle.
Fredericks had struggled in the opening 45 minutes and Johnson looked far more comfortable than the experienced defender and could well have done enough to usurp him in the pecking order.
