Schweinsteiger to undergo more surgery
The Germany international midfielder, who initially went under the knife in June, missed almost three weeks of action after being withdrawn with an ankle problem during the 1-1 draw with Freiburg in August.
And although he subsequently returned to full training to take his Bundesliga appearances to 10 matches for the reigning champions so far this term, the 29-year-old admits that he has still been struggling with the complaint.
"The last few weeks for me were always very painful," Schweinsteiger said in a statement on Bayern's official website.
"I tried it again, but I am now at a point where surgical intervention can no longer be avoided.
"I hope that I can be completely free of pain after the surgery play football again."
Bayern have not yet put a timescale on Schweinsteiger's return, but his absence is likely to be keenly felt by coach Pep Guardiola.
The Bavarian giants have yet to lose a game in the Bundesliga this season, and sit at the summit of the table with 29 points from 11 matches.
Their defence of the UEFA Champions League has also started brightly, with Bayern confirming their participation in the round of 16 with a 1-0 victory at Viktoria Plzen on Tuesday, which ensured an unassailable nine-point gap to third-place CSKA Moscow.