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. Article continues below Editors’ Picks Man Utd ready to spend big on Sancho and Haaland in January Who is Marcus Thuram? Lilian’s son who is top of the Bundesliga with Borussia Monchengladbach Brazil, beware! Messi and Argentina out for revenge after Copa controversy Best player in MLS? Zlatan wasn’t even the best player in LA! “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.Juve currently top both Group A in the Champions League and Serie A, winning all nine of their matches in the two competitions.