The luckless left-back had initially been withdrawn at half time of the 2-1 win over Aston Villa on February 11, which Erik ten Hag revealed at the time was a precautionary measure.
Shaw was given the green light to line up against Luton Town the following week, but once again, Victor Lindelof had to take the 28-year-old's place for the second half of that 2-1 success.
Rather than cede his place to Lindelof at half time, though, Shaw had to be withdrawn in the dying embers of the first 45, and Ten Hag admitted that the former Southampton man appeared to have sustained something severe.
A medical update from Man United has confirmed the worst, and Shaw is at risk of missing the remainder of the season with his muscular problem, but further tests are needed to determine the full length of his absence.
«Luke Shaw has sustained a muscle injury and will be out for an extended period,» Man United said. «Further assessment is still needed to determine the severity but we expect him to be absent for a few months.»
With the England international likely to spend the remainder of the campaign on the sidelines, he is set to miss a plethora of blockbuster Premier League games, including clashes with Manchester City, Arsenal, Chelsea and Liverpool.
The Red Devils are still competing for FA Cup glory and will face Nottingham Forest in their fifth-round tie on February 28, before the quarter-finals — which Shaw will also miss — take place in the middle of March.
The defender will not be available for April's semi-finals should Ten Hag's men get that far, and with the final scheduled for May 25, it remains to be seen
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