The battle for MotoGP race wins won't come down to just the 'big four' in 2011, according to one of the 'aliens' himself Casey Stoner.

The 2007 champion embarks on a new chapter in his career after switching to Repsol Honda, though his impressive pace in testing suggests he already begins the 2011 season as a title favourite.

Despite this, Stoner is anticipating a close-fought battle for race victories in 2011 beyond the 'aliens', a nickname given to Stoner, Valentino Rossi, Jorge Lorenzo and Dani Pedrosa by Colin Edwards, due to their domination of the 800cc era.

Identifying Honda counterparts Marco Simoncelli and Andrea Dovizioso as being amongst the candidates to challenge for wins this year, he also added Yamaha's Ben Spies to the list of those likely to be a consistent Sunday threat.

"I expect some surprises, although I did the same last year and there were the same four riders winning races and getting on the podiums," he said. "I am certain Dani and Jorge will be in front, but Andrea is quickly improving and also Simoncelli and Ben Spies can increase the list. I am sure that there might be some unexpected rider that will make an effort to be in front".

Regarding arch-rival Rossi, who has had a modest start to his Ducati career in testing, Stoner is not counting out his foe.

"Valentino might be ready for the first race, but we might have to wait a little."

With his Repsol Honda race debut around the corner, Stoner remains cautious about his chances in Qatar, despite his strong performance in testing and impressive record at Losail.

"I am very excited, because we spent many days training, but that is not the ideal situation, as during the pre-season we don't have a wide variety of circuits. Nevertheless, the races are finally approaching and I am looking forward to see how we perform with this team, how I work with the bike on the circuit and, above all, which is the general level for everyone.

"I am sure there will be riders more confident than others, so it will be interesting to see who goes for victory in the first race."

Since 2008, only Dovizioso has broken the 'big four' stronghold on race wins with victory at the 2009 British Grand Prix.