Juventus midfielder Sami Khedira is a doubt for the Champions League trip to Manchester United after tearing a thigh muscle.

The Germany international has been left out of the Juve squad for this weekend's Serie A clash with Udinese after undergoing medical checks on the problem.

"Latest tests have revealed that Sami Khedira suffered a tear of the flexor muscles in his left thigh," the club said in a statement.

"The German midfielder has already started therapy and will undergo further check-ups next week."

The injury leaves Khedira a doubt for the meeting with United at Old Trafford on October 23, with the return fixture on November 7 in Turin.

He could also be at risk of missing Serie A games against Genoa, Empoli and Cagliari, while the reigning champions travel to face AC Milan on November 11.

The 31-year-old has made six appearances in all competitions this season, scoring once.