Sam Allardyce is facing a team selection dilemma after in-form new signing Cheikhou Kouyate was ruled out for up to six weeks with a groin strain.
The summer signing from Anderlecht could be out for up to six weeks after being diagnosed with a groin strain by the club doctors at Upton Park.
“The 24-year-old has subsequently been diagnosed with a Grade Two sprain, which has left the player in moderate discomfort and will initially limit his ability to run and jump,” a statement on the West Ham United website said.
He will now begin rehabilitation work on the problem, which will begin with swimming pool exercises, before treatment will move into gym work the following week.
As well as missing the Manchester United match, Kouyate will also be potentially sidelined for trips to Burnley, Stoke and Everton, as well as home fixtures against QPR, Manchester City and potentially Aston Villa.
Signed from the Belgian club over the summer in a deal worth €9 million, the Senegal international has excelled in his brief Premier League career to date and the Hammers could struggle to fill the void left by his absence.
In the short term, manager Sam Allardyce will be aiming for a repeat of the heroics that saw his team outclass Liverpool when they meet a Manchester United side with just one win to their name in the top-flight so far this season.