Midfielder Paul Scholes sustained a knee ligament injury in the first half of Manchester United's Champions League match against Aalborg tonight.
The former England international had to be substituted after 16 minutes of the game in Denmark following a challenge with Thomas Augustinussen.
Ryan Giggs came on as his replacement, and Scholes could now face a lengthy lay-off.
Manager Sir Alex Ferguson confirmed on ITV4: "He's got knee ligament damage.
"We don't know how serious it is obviously.
"We'll have it assessed as soon as we get home."
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