The 28-year-old defender is a mainstay of Erik ten Hag’s side and started the first two Premier League matches of the season.
But Shaw will miss Saturday’s Old Trafford encounter against Nottingham Forest and next weekend’s trip to Arsenal as well, it seems, as England’s upcoming internationals.
The left-back is facing a number of weeks out with a muscle injury that is still being assessed.
A club statement read: "Manchester United defender Luke Shaw has sustained an injury which will rule him out of forthcoming games.
"The muscle issue is still being assessed but the England left-back is expected to be out of action for a number of weeks."
United and England will be hoping nothing worse crops up during those assessments, especially with fellow left-back Tyrell Malacia also sidelined through injury.
The Old Trafford club loaned out another left-back earlier on Thursday, with Brandon Williams joining Ipswich for the remainder of the campaign.
United had already announced an injury to Mason Mount ahead of the Forest match and it remains unclear whether new boy Rasmus Hojlund will be fit to make his debut.
Amad Diallo, Kobbie Mainoo and Tom Heaton are also out, while Harry Maguire missed the trip to Spurs with a knock.