The former Chelsea winger is considered a more influential figure than Franck Ribery at the Allianz Arena, following crucial goals against Fiorentina in the Champions League and Schalke in the German Cup, and is being given injections and massages after limping off with a calf injury against Stuttgart on Saturday.
Injury doubt: Bayery Munich's Arjen Robben may miss the Champions League match against Manchester United
Bayern insiders rate his chances of facing United as 'less than 50-50'.
Full back Philipp Lahm admitted the loss of Robben would tilt thetie United's way, saying: 'When you consider the importance of thosegoals against Fiorentina and Schalke, there is no doubt it will beharder than ever for us, if Arjen is ruled out.'
Striker Mario Gomez trained on Sunday after three weeks out, and is expected to be available.
Ribery reiterated that he will snub Chelsea and United and choosebetween Real Madrid and Barcelona if he leaves Bayern in the summer.
'My wife does not like the weather in Germany. We cannot go toEngland. The choice is between staying at Bayern or moving to La Liga,'
Danger man: Arjen Robben in action for Bayern Munich against Stuttgart
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