Rossi not planning to retire soon

"It's 100 percent certain I will race in 2009, unless I win every race next year," the Italian told Motosprint magazine.

"I've never considered quitting, otherwise I would have done that in 2006 and maybe I would have gone to Formula One. But I didn't, and it's not just for one or two years.

"I'm staying, I hope, for at least five years."

The 28-year-old Italian has a year of his Yamaha contract left to run and will be hoping to bounce back in 2008 following a disappointing 2007 season.

Rossi won just four races to champion Casey Stoner's 10, and the Yamaha rider went on to finish in third place in the standings behind the Australian and Honda's Dani Pedrosa.

The five-time MotoGP champion admits it has been tough watching Stoner being the fastest rider on track.

"For sure this hasn't been one of my best seasons," he added. "It's been a tough year, different from the previous one when I was often the fastest but I lost through mistakes and bad luck. This year Stoner has always been quicker than us, bar a few exceptions.

"It's been tough. Casey has gone quick and hasn't made mistakes, and that's been a surprise, because we knew already he was quick. He fully deserves the title. We will try to challenge him in 2008."