The 24-year-old is on a season-long loan at Upton Park but has sustained a knee problem and may force the Hammers to dip into the transfer market to acquire a replacement
West Ham loanee Gokhan Tore will undergo a scan on Friday to determine the extent of an injury suffered in training.
Tore - on a season-long loan from Turkish outfit Besiktas - sustained a knee problem in a light session on Monday.
The winger then missed out on West Ham's 2-1 defeat to Slovenian side Domzale in their Europa League qualifying third round first leg on Thursday.