United are already without the likes of Amad Diallo, Lisandro Martinez and Matthijs de Ligt among others due to fitness issues, and the loss of the 23-year-old leaves Ruben Amorim relying on Rasmus Hojlund as the only senior striker available. Beyond him, Amorim could bring 17-year-old Chido Obi back into the fold.
DID YOU KNOW?
Zirkzee has managed just three Premier League goals this season, having started 14 of his 32 appearances in the competition, while he has netted two in the Europa League.
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WHAT NEXT FOR ZIRKZEE?
Zirkzee's injury comes just days ahead of United's clash with Lyon in the quarter-finals of the Europa League. The two sides are level at 2-2 after the first leg in France.