Franck Ribery has admitted that the knee injury sustained by David Alaba is a "catastrophe" for Bayern Munich.

Alaba is expected to miss up to seven weeks after damaging his knee ligaments on international duty with Austria, and Ribery believes that getting his versatile teammate back on the pitch before the end of the season could be key as Bayern look to clinch a treble.

"It is difficult for him, for his family, for the team and for the whole club. He is so important for us," the French winger told Goal.com.

"He was already injured before the winter break, but he fought back. He was in peak condition and his performances were great. We have lost a big player.

"Now he has to stay calm and remain optimistic. David is strong enough to deal with it. For us, though, this is a catastrophe. He must return as soon as possible, he's that important to us."

Bayern return to action against Borussia Dortmund on Saturday.