Doha: Australian Casey Stoner will lead the charge of the young guns pursuing world champion Valentino Rossi as the MotoGP season kicks off under floodlights at the Grand Prix of Qatar.
Stoner, 24, the 2007 world champion, had a strong finish last season after missing three races because of illness, finishing second in Portugal and winning in Australia and Malaysia.
His confidence is high at the Losail circuit where he has won for the past three seasons, and was the fastest rider in the final winter testing session in March.
"If Casey is physically in form, if the Ducati works as we're expecting it to, both are going to give us serious problems," Yahama managing director Lin Jarvis told AFP.
Yamaha have a hard act to follow last season when Rossi led a 1-2 ahead of teammate Jorge Lorenzo, and they also won the constructors title.
Rossi, who has seven MotoGP titles, can expect a serious challenge from the young generation including Stoner (Ducati), American Ben Spies (Yamaha Tech 3), Lorenzo (Fiat Yamaha) and Daniel Pedrosa (Honda).
Rossi, 31, admitted: "I think there will be a big battle. There are a lot of new riders with a lot of ambition. Particularly Ben Spies but also [Italians] Marco Simoncelli [Honda] and Andrea Dovizioso [Honda]."
The Italian added: "Qatar is a track which didn't really suit our bike in previous years but the test went very well and we hope to continue like that."
Stoner said he was feeling confident ahead of Qatar.
"We have always enjoyed great results in Qatar although the track isn't one of my favourites as a rider," Stoner told MotoGP.com.
"I will give my maximum as always but it's only the first race in a very long season that will only start to take shape from the third or fourth round."
He added: "It was good that they changed the race from daytime to night because they've made it different to anything else — it's interesting for the fans and it's good fun for us."
The new rules which allows stables to use just six engines for the entire season of 18 Grand Prix could see new riders emerging.
Spies, 25, the reigning world Superbike champion, will be competing with French outfit Tech 3, along with US veteran Colin Edwards, fifth last season.
"An indepedent team like ours is always a little bit behind in relation to development compared to a factory team but I think the differences will be extremely reduced with this new rule," Tech 3 boss Herve Poncharal told AFP.
Japan's Hiroshi Aoyama, the 250cc world champion in 2009, will step up to MotoGP this season with Honda.
