Manchester United captain Wayne Rooney could miss Sunday’s game with Sunderland at the Stadium of Light due to ankle problems.
The 31-year-old has found playing time hard to come by this season, although may well have an important role to play during a chaotic end to the campaign.
United had to do without Rooney against former club Everton as ankle pain kept him out of Tuesday night’s 1-1 draw.
Jose Mourinho has confirmed the issue also means the club’s all-time top scorer is facing a race against time to be fit for Sunday.
"Two ankles, so I don’t know," the United boss said.
"But I don’t think it is so easy to recover in a couple of days."
Asked if the injury was sustained in training or just an after-effect, Mourinho added: “After the game [against West Brom]”.
Chris Smalling, Phil Jones and Juan Mata are others definitely out of the Stadium of Light clash through injuries Mourinho says will keep the trio out for a “long time”.
Antonio Valencia, who has impressed at right-back this season, is set to return after being rested against Everton.
Sunderland’s bleak survival hopes took another heavy blow with the 2-0 defeat to Leicester City ahead of David Moyes facing his former side on Sunday lunchtime.
United have struggled at home this season, with nine draws to their name, but they remain unbeaten in 20 Premier League matches after coming from behind to draw with Everton, top scorer Zlatan Ibrahimovic converting a late penalty.