Northern Ireland defender Jonny Evans will be sidelined for the "next few weeks" due to a thigh strain he suffered in the first half of United's 4-3 Champions League defeat at FC Copenhagen.
Manchester United said late on Friday.
He joins a lengthy injury list at United, who remain without defenders Lisandro Martinez, Luke Shaw, Tyrell Malacia and midfielder Casemiro.
The 35-year-old will miss Northern Ireland's final Euro 2024 qualifiers against Finland and Denmark. Northern Ireland, who sit fifth in Group H with six points, travel to Finland next Friday before hosting Denmark on November 20.
Evans rejoined United on a one-year deal in September, eight years after leaving Old Trafford and has started five league games.
United lie in eighth place in the top-flight after picking up 18 points in 11 matches and host promoted Luton Town later on Saturday.
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