Bayern Munich are sweating on the fitness of Mats Hummels for Wednesday's Champions League home clash against Real Madrid after the Germany defender injured his ankle in training on Sunday.

The centre-back was left on the bench for Saturday's 4-1 Bundesliga drubbing of Borussia Dortmund in Munich having been rested by coach Carlo Ancelotti for the quarterfinal, first-leg, match against Real.

But Hummels let out a cry after injuring his right ankle in Sunday's training session and was taken away on a golf cart after treatment, leaving Bayern waiting to see how bad the injury is.

There is some good news for Bayern as Germany forward Thomas Mueller was back in training after missing their last two matches with an ankle injury, while Germany goalkeeper Manuel Neuer faces a race against time to be fit to face the Spanish giants and has not yet resumed training after a minor foot operation.