Goalkeeper Andre Onana will return to Manchester United to discover the extent of an injury sustained playing for Cameroon in a World Cup qualifier.
Onana, 27, was substituted in the 81st minute of Friday's 3-0 victory over Mauritius in Douala, having been injured making a save.
The goalkeeper has pulled out of Cameroon's squad for Tuesday's match against Libya.
Cameroon officials did not give details of the type or severity of the injury.
Onana, signed from Inter Milan for £47.2m, has played in all 18 of United's competitive fixtures so far this season.
United manager Erik ten Hag is already facing several injury issues as his squad prepare to return from the international break with a Premier League trip to Everton on November 26 and a Champions League visit to Galatasaray three days later.
Lisandro Martinez (foot), Casemiro (thigh) and Christian Eriksen (knee) are all definitely out while Luke Shaw (muscle problem), Jonny Evans (thigh), Tyrell Malacia (knee), Aaron Wan-Bissaka (illness) and Rasmus Hojlund (thigh) are facing a race to be fit in time.
