Manchester United expect to be without right-back Aaron Wan-Bissaka for up to two months after he picked up a hamstring injury late in the 3-1 defeat to Brighton & Hove Albion.
Having started the team's first four games, Wan-Bissaka dropped to the bench against Brighton after battling illness during the week, but he managed to come off the bench for the final five minutes of the game.
During that brief cameo, Wan-Bissaka picked up a hamstring injury which United admitted will keep him sidelined for "several weeks".
According to The Athletic, Wan-Bissaka's absence period could be as long as two months.
With a potential return date in mid-November, Wan-Bissaka appears set to miss as many as seven Premier League games, including the Manchester derby on 29 October, as well as the team's first four Champions League group games.
United kick their European campaign off against Bayern Munich on Wednesday, with Diogo Dalot now expected to start.
United boss Erik ten Hag is battling a major selection headache as Wan-Bissaka becomes the third full-back to pick up an injury.
Left-backs Luke Shaw and Tyrell Malacia are both sidelined, with Dalot often filling in on the left, but summer signing Sergio Reguilon now appears set for a significant run in the team as United battle a hectic run of fixtures.
Goalkeeper Tom Heaton remains sidelined alongside midfield duo Kobbie Mainoo and Mason Mount, while winger Amad Diallo is also out through injury.
Ten Hag is also without Antony and Jadon Sancho. The former is in Brazil battling assault charges, while Sancho has been banished from the first team after refusing to apologise for his social media post slamming the boss' treatment of him.
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This article was originally published on 90min as Man Utd learn extent of Aaron Wan-Bissaka hamstring injury.