Retired rival Loris Capirossi says Valentino Rossi is still the class of the field

Capirossi also believes Rossi will rediscover the winning touch, despite ultimately failing in his project to make the Ducati a winner - for which Capirossi, who spent five seasons riding the Desmosedici, blames Ducati rather than Rossi.

"Valentino has done the right thing, because he's still the best and he knows that well, and because with Ducati you can't win anymore, at least not at the moment," Capirossi told Repubblica.

"I'm with Rossi, as is the entire MotoGP world, which needs a shake-up and to find again enthusiasm as soon as possible. It needs its champion, its hero, to return to the top.

"The best-loved rider can't be limited to a supporting role. We all need pure adrenaline, which is what we have perhaps lacked these last few years. Let's not kid ourselves, there's no one like him. He is a blessing for this sport.

"He couldn't carry on, I'm sorry for Ducati, but perhaps the end of this love story will teach everyone something. They didn't manage to keep up with the times.

"Valentino is right: they would talk about numbers, technical analysis, tables, without listening to the guy on the bike. For too long they had thought the problem was the rider, but it wasn't."

Having partnered Casey Stoner when the Australian won the title for Ducati, Capirossi said the bike was fundamentally different to the model Rossi had been able to ride.

"[Stoner's] was a different bike. The year he won the title I won a race too and got on the podium twice," he said. "I'd really like to see what Stoner would do with today's Ducati."

Rossi's return is not the first time a previous champion has returned to a former team - four-time champion Eddie Lawson rejoined Yamaha in 1990 but failed to add to his collection of world championship crowns.

Despite that, Capirossi is tipping Rossi for next year's title, adding: "It's true [that talent is not the only factor], but Valentino has more talent than anyone. Lorenzo is good too, but I already have my favourite for next year."