Alaba, Austria's Player of the Year last season, came off markedly worse having been ruled out for six to eight weeks after suffering a stress fracture.

Further tests will be conducted on Monday to ascertain the full extent of the damage and decide whether an operation is necessary.

Rafinha also suffered an injury during the friendly and has torn ankle ligaments. He will not require an operation, but will nevertheless miss the next four to five weeks, making him a doubt for the beginning of the new campaign, which kicks off on August 25.

Both have been excluded from the Bavarians' pre-season trip to China on Sunday, according to the club's official website.

Philipp Lahm and Bastian Schweinsteiger have also been deemed unavailable for the tour so they can concentrate on "building up their fitness" for the new term, according to coach Jupp Heynckes.