Former MotoGP champion Casey Stoner insists he will be ready for a title challenge next season after his winter surgery.

The 23-year-old Marlboro Ducati rider saw Valentino Rossi end his year-long reign at the top of the sport last month but is still set for second in the championship ahead of this weekend's final round at Sepang.

Stoner will then take part in a test of next year's Ducati before undergoing surgery on his troublesome wrist injury and the Australian is confident that he will push Rossi all the way again next season.

He said: "The Valencia test is the thing we're really focussing on now.

"I really want to get those first two days done, get as much information on the bike as we can so the changes that we need to make can be ready for the beginning of next season.

"We believe that we're going to be quite strong again next season, at least to try and fight for the championship, so we need to start as soon as possible.

"If I got the operation done any sooner then it would be difficult to only have testing from the beginning of next year.

"It's going to take time for me to come back to full fitness, but I think that by the time racing starts next year I should be ready."

Stoner, winner of five races so far this season, reiterated that the operation is essential to his future.

He said: "Unfortunately the operation has to be done.

"I'd love it all to just repair itself and go on happily, but unfortunately we need to get it done.

"For me, I think we're quite lucky to have found it now. This season hadn't gone the way we'd planned it, I made a few mistakes, so it's better that we found it this season and can get ready for a better attack next year."