Robert Lewandowski has missed two days of training in a row
Lewandowski picked up a shoulder injury in Bayern's 4-1 win over Borussia Dortmund on Saturday.
The Polish hitman scored twice against his old club but was forced off when he collided with keeper Roman Burki.
Boss Carlo Ancelotti claimed yesterday he'd be fit for the game.
But Spanish newspaper Marca are this afternoon reporting he is still a serious doubt after missing training for the second day in a row.
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Speaking after Saturday's win, Ancelotti tried to play down the extent of the injury.
He said: 'Lewy sustained a bruise, but the medical unit says it's no problem with regard to Wednesday."
Lewandowski echoed Ancelotti's sentiments and added: "It's not too bad. I didn't want to take any risks, and I'll prepare well for Wednesday."
There was better injury news for Bayern over Manuel Neuer, who returned to training today from a for injury.
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