Manchester United midfielder Casemiro has reportedly emerged as a doubt for Thursday's fixture against Real Betis.
United play Spanish opposition for the third time in the Europa League this season having faced Real Sociedad in the group stages and Barcelona in the playoff round.
However, Erik ten Hag's side head into the first leg of their last-16 tie at Old Trafford having suffered an embarrassing 7-0 defeat to Premier League rivals Liverpool.
Six of the goals at Anfield came in the second half, ending any momentum that United had built from winning the EFL Cup late last month and progressing through to the quarter-finals of the FA Cup.
Casemiro has emerged as one of United's key men since moving from Real Madrid in August, making a total of 27 starts and eight substitute outings in all competitions.
Despite suggestions that United are becoming fatigued due to a lack of rotation from Ten Hag this season, Casemiro would have been expected to be named in the starting lineup on Thursday.
While that may still be the case, ESPN claims that his participation is far from a certainty due to injury.
After a below-par showing on Merseyside, it was speculated that the 31-year-old had been carrying some kind of issue during the capitulation in the second half.
Casemiro was substituted with 14 minutes remaining, but that withdrawal could have been at least partly down to Ten Hag wishing to rest key players with the match having already been lost.
A source is said to have informed the outlet that Casemiro is currently being assessed by the club's medical staff to determine whether he can play any part against Betis.
Should Casemiro be ruled out, it would represent a blow to United with the player having been sufficiently rested during a three-match ban served in the Premier League during February.
Either Scott McTominay or Marcel Sabitzer would come into the team to replace Casemiro if required, with Fred retaining his spot in central midfield.
United also play Southampton and Fulham before the international break, either side of the reverse fixture with Betis on March 16. body check tags ::
