Manchester United defender Raphael Varane sustained a hamstring injury in their Champions League draw with Atalanta on Tuesday and will be out for around a month, the club said on Wednesday.
The 28-year-old France international started the match as part of United's three-man central defence partnership, but had to be replaced in the opening half.
Varane only returned to the team for last weekend's 3-0 victory over Tottenham Hotspur after overcoming a groin injury sustained on international duty last month.
He completed a reported 34 million-pound ($46.5 million) move to United from Real Madrid this summer.
United drew 2-2 with Atalanta thanks to Cristiano Ronaldo's two goals and top Group F with seven points after four matches.
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