West Ham were today left to assess the damage after their shirt sponsors were placed into administration.
The collapse of XL Holidays, West Ham's principal partner, midway through a three-year contract worth £7.5million has forced the club to seek talks with administrators.
West Ham are believed to have been paid just £2.5million to date, leaving them facing a £5million shortfall during a time of financial uncertainty at Upton Park.
XL Holidays branding will be retained for tomorrow's clash with West Brom with an update on the club's position expected next week.
A statement read: ''West Ham United were informed today that XL Leisure Group, which operates the club's principal partner XL Holidays, has been placed into administration.
''XL Holidays remains the club's principal partner and we await further information from the administrator before ascertaining the impact of today's events.
''We are of course saddened for the customers of XL Holidays that they have been affected and hope that a speedy and satisfactory solution is found.''