Manchester United defender Luke Shaw is facing several weeks on the sidelines with a hamstring injury sustained in Saturday's win at Everton.
The left-back limped off late in the second half at Goodison Park, with manager Ole Gunnar Solskjaer admitting at the time he looked "in a bad way".
United now say Shaw, who has started seven matches in 22 days, will be out for a month.
In a statement they said he "could miss upcoming Premier League games against West Brom, Southampton and West Ham, as well as Champions League clashes with Istanbul Basaksehir, Paris St Germain and RB Leipzig".
In terms of options the manager has Alex Telles, who has been restricted to one appearance following his move from Porto in October due to a positive Covid test, Brandon Williams and Axel Tuanzebe.
United did not offer updates on the fitness of defender Victor Lindelof (back) and Marcus Rashford (shoulder) who were also injured in the Everton game.
The pair are still scheduled to join up with Sweden and England respectively for international duty.
News on Shaw's absence will not have improved Solskjaer's mood, on after Saturday's win criticised the fixture schedule which saw them kick off at 12.30pm having returned from their Champions League fixture in Turkey at 4am on Thursday as an "absolute joke".
"How can you expect players to perform to the best of their ability when you send them out at 1230?" he said.
"They are not robots, they are human beings and they are asked to perform."
