Striker Michail Antonio is a doubt for West Ham's Europa Conference League match against Anderlecht on Thursday.
The Hammers are top of Group B and will advance as group winners if they beat the Belgian side and Danish team Silkeborg fail to beat FCSB of Romania.
West Ham won 1-0 in Belgium last week, thanks to Gianluca Scamacca's goal.
"Micky Antonio has had a wee bit of cold, or the flu, which has kept him out of training a day or two," said Hammers boss David Moyes.
"We're a little bit unsure on him. We've got a couple of knocks and niggles but hopefully, he will be OK.