Marcos Rojo will undergo a late fitness test to see if he can play against Tottenham on Sunday, with Manchester United facing the prospect of being without two of their four senior centre-backs.
Rojo, 24, has a "minor problem" and Louis van Gaal, who is already without the suspended Jonny Evans, is unsure if he will be available for the game at Old Trafford.
"Rojo is a little bit injured and you have to take care of the health of players," Van Gaal told MUTV. "He has a minor problem. Maybe I take him out of the game against Tottenham but I have to decide."
Phil Jones and Chris Smalling are the only experienced centre-backs who are definitely available, although Van Gaal also has the option of youngsters Tyler Blackett and Paddy McNair, who were both given debuts by the Dutchman.
United's only definite absentee because of injury is striker Robin van Persie, who will be sidelined for a fourth successive game by the ankle problem he sustained at Swansea on Feb. 21.
However, Angel Di Maria will also be missing as he is suspended following his sending off in Monday's 2-1 FA Cup quarterfinal defeat to Arsenal.
Meanwhile, Van Gaal says he is impressed with the way Tottenham boss Mauricio Pochettino has made his mark at White Hart Lane by promoting younger players.
Harry Kane has won back-to-back Player of the Month awards in the Premier League, and Van Gaal singled out the forward for special praise.
"It is the first match of the 10 matches we have to play in the rat race," he added in his news conference. "It is not easy to play Tottenham because I like Tottenham, I like the process in Tottenham. A lot of experienced players are not playing and a lot of youngsters are playing.
"In spite of that they are very close and they are playing attacking football. The way their striker [Kane] is scoring is a reason for their success. It is also an aspect in the world of football that a big talent can stand up in one season and he is doing that."