Robert Lewandowski will be out for "around four weeks" after the Bayern Munich forward picked up a knee injury during Tuesday's 3-0 Champions League demolition of Chelsea, the Bundesliga leaders announced on Wednesday.

In a statement, Bayern said that club doctors had discovered that Poland striker Lewandowski had "fractured the tibia where it meets the left knee joint" following tests after their return from London.

The 31-year-old, who scored his 11th Champions League goal this season as Bayern ran out easy winners at Stamford Bridge, will miss the return leg in Munich next month and likely three rounds of matches in the Bundesliga.

Lewandowski is having one of the best seasons of his career. He is top scorer in the Bundesliga with 25 league goals in 23 appearances and in the Champions League, in which he is three ahead of teenage sensation Erling Braut Haaland.

His 76th-minute strike in London ended his seven-match drought in the competition's knockout stages.

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