The England midfielder has only recently returned to action for the Bundesliga club after four months out with a broken leg.

Hargreaves collected his latest knock in the 3-2 first-leg defeat against Real at the Bernabeu last week and has not trained fully since.

The 26-year-old nevertheless played in Bayern's league win over Wolfsburg last weekend, but on Tuesday he left training early to undergo tests with Bayern's club doctor.

Hargreaves is unlikely to feature in Saturday's league match at Hertha Berlin, but Bayern remain hopeful that he will be back in time for the return leg against Real on March 7.