Giacomo Agostini, the most successful granꦯd prix motorcycle racer of all time, d🃏oubts Valentino Rossi's chances of claiming a tenth title.

'Ago' won 15 championships in all▨ classes during the 1960s and '70s, including a record eight in the premier 500cc class.

Rossi, who already holds the record for most 500cc/MotoGP wins, is just one title short of Agostini in the premier-class, and also claimed previous hon🦩ours in the 125 and 250cc series.

After two winless seasons at Ducati, Rossi is returning to Yamaha - with w🌠hom he enjoyed the majority of his MotoGP success.

Agostini believes Rossi can still be a formidable opponent, but isn't sure 𒐪he can overcome the likes of team-mate🧸 and reigning double champion Jorge Lorenzo.

GPone.com quotes Agostiꩲni as saying: "I'm convinced that Valentino Rossi isn't ꦬfinished as a racer, but I think it will be difficult for him to win the next championship."

"It has been two years since Valentino won a race, and three since he last won a world title, in 2009. Bey🌌ond that, he is als💖o two years older.

"A🌳ge does matter - otherwise I would still ඣbe racing!"

Angel Nieto, a 13-time title winner in t𝔉he 125 and 50cc classes, is the only rider between Agostini and Rossi on the list of all time championship wins.

Rossi will be 34 by the start of the 2013 MotoGP seas𒅌on.