Michael Schumacher's manager admits it is "possible" the former seven time world champion will finally part ways with Ferrari at the end of 2009.

Since he retired at the end of 2006, 40-year-old German Schumacher has occasionally tested the Maranello team's single seaters, and attended several tests and grands prix in an advisory role.

His latest appearances were in Australia and Malaysia, whereafter Ferrari figures were heavily criticised for making bad strategies and decisions on the pitwall.

"It astonishes me that with such an advisor such a shambles could occur," ex-driver Marc Surer is quoted as saying by the German press.

Elements of the German media were even more critical of the role Schumacher should have played in preventing the messes, including the one last Sunday when Kimi Raikkonen was sent onto the dry Sepang track with full wet tyres.

Schumacher's estimated 5m euro per-year contract is due to expire at the end of this year.

"If the contract isn't renewed I'm certain that the Malaysia grand prix will have nothing to do with the decision," his manager Willi Weber told the SID news agency.

He said talks with Ferrari will only take place in the second half of the season.

It has been rumoured that if Schumacher does leave Ferrari, the path will be clear for him to reunite with his former technical director and strategist, Ross Brawn.

Brawn GP driver Jenson Button dismissed the speculation.

"We have been around long enough to know what it takes to win," the Melbourne and Malaysia winner said.