Stoner won last time out at the Czech MotoGP in Brno

The Ducati rider has a 60-point lead over Valentino Rossi with six rounds left going into Sunday's race.

The only rider to have previously missed out on the world crown while holding such a big advantage is another Australian, Mick Doohan.

The five-time 500cc champion led by 65 points with five races left in the 1992 season before getting injured.

Yamaha's Rossi, another five-time top-class champion, is not giving up in his pursuit of Stoner.

He has won the last six Italian Moto GPs in a row at Mugello but the San Marino race is more of homecoming as Misano is close to the town of Tavullia where he grew up.

"I want to win to give some joy to my fans," said the 28-year-old who feats are largely responsible for a second Italian race being added to MotoGP's calendar.

"We are in the process of finding the miracle tyres that we have been searching for," he added.

"We have gathered some information that we hope will be useful to Michelin."

Misano, which last hosted premier class motorcycling in 1993, has been criticised by some riders - including Stoner - as being too bumpy.