The Switzerland international was heavily linked with a move to Liverpool during the summer but a move to Anfield didn’t materialise.
Shaqiri has also been touted as a possible target for Borussia Dortmund as the speculation surrounding his future continues.
Now, Beckenbauer has hinted that the Germany club would consider selling the 23-year-old in January if he does not improve his attitude.
“Bayern have sent some signals to the boy, who can leave the club once the window opens,” Beckenbauer told Sky Deutschland.
“Personally I want players at the club who want to stay with us and if a player wants otherwise, he is free to leave for another team.”
Shaqiri has been limited to just three Bundesliga starts this season, scoring one goal and making two assists.
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