David Moyes revealed Shinji Kagawa sat out Sunday’s game against Cardiff with a bruised foot sustained on international duty with Japan.
Kagawa was one of "four or five key players" missing from Moyes’ side in the Welsh capital, with Nemanja Vidic (concussion), Robin van Persie and Phil Jones (both groin) among the other absentees.
While Kagawa played in both of Japan’s friendlies during the international break, van Persie did not take part in either of the Netherlands’ games.
Jones, meanwhile, could be in contention to return in the Champions League at Bayer Leverkusen on Wednesday, a game Marouane Fellaini will miss through suspension.
"Kagawa got injured playing for Japan," Moyes said at his post-match press conference. "It’s an injury to his foot; there’s some bruising there, but it’s not too bad.
"Robin’s groin is the problem at the moment; his toes are much better. We are hoping to get both Nemanja and Robin back as soon as we can.
"I hope they'll be in contention for Wednesday but I couldn’t give you a definitive answer."
When asked if Jones could feature in Germany, Moyes added: "Possibly. I don't think he is as bad as we first thought. He's not too far away. It's a groin injury, right up his hip."
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