Honda MotoGP rider Casey Stoner of Australia holds the Japan flag while paying tribute to the people killed during the earthquake and tsunami, after the Qatar Grand Prix at the Losail international circuit in Doha March 20, 2011. [Photo/Agencies]

DOHA - Australian Casey Stoner won the floodlit Qatar MotoGP season-opener for the fourth time in five years on Sunday ahead of Spaniards Jorge Lorenzo and Dani Pedrosa.

Starting from pole position after dominating all three practice sessions, Stoner beat Yamaha's world champion Lorenzo by 3.44 seconds at the Losail circuit in a dream debut with the works Repsol Honda team.

The Australian, who raced for Ducati last year, has now won 24 grands prix in the top category.

Spain's Pedrosa, Stoner's Honda team mate, was struggling with a painful arm and looked exhausted after finishing just over five seconds behind the Australian, despite taking the lead on the opening lap and fighting an entertaining duel to the halfway point.

Valentino Rossi of Italy, winner of nine world titles across the classes but struggling with a shoulder injury, finished well off the pace in seventh in his first race with Ducati after leaving Yamaha.

"Definitely, it couldn't be any better," Stoner, the 2007 world champion, told reporters.

"It's a similar start to what we had when we won the world championship....we've had some fantastic starts to the season but everything with Honda so far has been just amazing, everything we've done with the bike over the pre-season," he added.

Lorenzo Delighted

Lorenzo had warned that Stoner and Pedrosa were the men to beat, with Honda fastest at every pre-season test, and had said he would be happy to be on the podium.

The Mallorcan exceeded his own expectations and his delight was evident as he punched the air repeatedly as he cruised down the pitlane after taking the chequered flag.

On the victory podium, the Spaniard appeared the happiest of the three with the two Honda riders waving Japanese flags in solidarity with the victims of the devastating quake and tsunami.

"Not so many people thought about us for this race," said Lorenzo. "But we believed in ourselves every day, better and better. Today I put everything I have on the track, I didn't save anything. I was at the limit in every corner and every lap.

"I almost crashed. When you go like this it is very easy to crash."

Pedrosa took the lead at the start but was passed by Lorenzo while Stoner hit the front on lap two. The Spaniard overtook Lorenzo for second on the third lap and got back in front of the Australian for a brief stint.

His battle in the second half of the race was for second place, with the two Spaniards dicing with each before Lorenzo made his move stick with four laps remaining.

"In the middle of the race I started having a lot of problems again with my left arm," he said. "I couldn't control the bike any more and I just tried to slow down...I couldn't grip really good or use the clutch in the proper way."

Britain's Cal Crutchlow finished 11th on his MotoGP debut with 13 finishers.