Valentino Rossi says he is facing the "most difficult decision of my career" as he weighs up several offers ahead of the 2013 MotoGP championship.
The Italian explained his dilemma was based not only on assessing the relative strengths of each team, but also its riders - specifically Yamaha's Jorge Lorenzo, who he labelled the "best rider in the world."
Asked about his options for next year, Rossi told Gazzetta dello Sport: "This is perhaps the most difficult decision of my career, because I have to decide where and how to end my career. The decision is up to me, it doesn't depend on others.
"I have three proposals on the table and all three of them have positive and negative aspects. With one of them there would be more uncertainties on how quickly positive results come, while with the other two it should be easier to get them quickly."
Pressed about the possibility of him returning to Yamaha, where he enjoyed unprecedented success between 2004 and 2010, Rossi admitted Lorenzo's form made the decision harder than in 2003, when he switched from the works Honda team.
"Clearly that would be a difficult choice too, perhaps even more than the one I made in 2003," he said.
"Back then it was a matter of sorting out a bike that wouldn't go quick, while now it's a matter of beating the best rider in the world on equal machinery."
Rossi added that Ducati remains a strong option given Audi's involvement, saying: "We are talking [with Ducati], but we haven't got into technical details unfortunately... in fact scratch unfortunately: I'm proud that the new owner, Audi, wants to make this project a winner and wants to do it with me."
As Rossi ponders his options, Andrea Dovizioso, also linked strongly to the second Yamaha works ride, expressed his frustrations at having to play second fiddle to the seven-time champion.
"Yes, it is a bit upsetting, because you feel little consideration towards you," Dovizioso admitted. "It's normal that a rider, who has won a lot more than me, has more power but, as far as I'm concerned, I can't do more than I have.
"In the first nine races this year I've been quick and got on the podium four times with performances that probably no one had expected. I think it's legitimate to believe I should have great chances to get on a works bike, but unfortunately it's not the case.
"There won't be news here, we can only wait for Valentino's decision. I have set a deadline for myself, but I can't wait for Yamaha forever either. Ducati is an extremely interesting option, even though the bike is not a winner at the moment. But they have everything to improve."