West Ham defender Kurt Zouma will miss Thursday's Europa League quarter-final second leg against Lyon because of injury.
The France centre-back was forced off during the Hammers' Premier League defeat at Brentford on Sunday after hurting his ankle.
West Ham say the 27-year-old will remain in London to undergo further tests.
The tie is in the balance after last week's 1-1 draw at the London Stadium.
West Ham boss David Moyes is already without the suspended Aaron Cresswell, who was sent off in the first half of the opening leg.
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