West Ham midfielder Gary O'Neil will miss his embattled club's final five matches as they attempt to escape relegation.
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O'Neil damaged ankle ligaments during last weekend's defeat to Aston Villa following a challenge from former Hammers star Nigel Reo-Coker and has been forced to undergo surgery on the problem.
"It was a successful operation. I have got some joint damage in the ankle that they had to sort but I am told it went well," O'Neil told the club's official website. "I am disappointed not to be involved for the last five games but I am looking to get back as fast as I can next season. I will be right behind the lads and I'll be cheering them on at the matches.
"I have got my head around the timescales involved for my comeback. I have just got to keep my foot up for a few weeks and then take it from there."
With Scott Parker, newly named Football Writers' Player of the Year, absent with an achilles injury which will require an injection, West Ham are running low on midfield resources at a vital part of the season.