Bayern Munich coach Felix Magath says he does not know whether Michael Ballack will be at the club next season.
The 29-year-old, who is out of contract with Bayern at the end of the current season, has been persistently linked with a move to Manchester United.
Magath told the News of the World: “Ballack is a leader – to achieve that status at Manchester he will have to work his way up again.
“That is a challenge and maybe it is one he will look forward to.”
Bayern have offered Ballack a four-year extension – and are keen for the situation to be resolved as quickly as possible.
“I am not worried that Michael may be ready to go, but I just want the decision made,” Magath added.
“The most important thing for me is that he makes a choice soon.
“I want to put this behind us and concentrate on football.”
The Germany midfielder joined Bayern from Bayer Leverkusen in 2002, turning down Real Madrid in the process.
Ballack’s agent Michael Becker had previously dropped hints that the midfielder may be preparing to leave the Bundesliga club.
“Bayern took a long time putting their offer on the table,” Becker told Kicker magazine.
“It is only fair that we look around and see if this offer fits the market value.”