MOTEGI, Japan: Australian rider Casey Stoner won the Japanese Grand Prix Sunday, grabbing his second straight victory despite frustrating problems setting up his Ducati throughout the weekend. The 2007 world champion clocked 43min 12.266sec at the Motegi Twin Ring, 3.868sec ahead of pole-position starter Andrea Dovizioso and 5.707sec faster than reigning champion Valentino Rossi, both of Italy. Championship leader Jorge Lorenzo only came fourth, after losing a nail-biting battle with Rossi in the final stages of the race. Stoner, fresh from winning the Aragon Grand Prix last month, called the victory an “upset” after his team struggled to find the best setup for his machine in “a disaster weekend”. “It's obvious the bike really isn't perfect for this track. And to come out and still win this was just awesome for me and for the team and for everybody,” he said. “This was one of my most memorable wins,” he said, after fending off challenges from Dovizioso, who had his first career pole start. The Honda rider lamented his accumulation of small mistakes that prevented him really threatening the Australian, but said he was happy to take second. “I wasn't precise 100 percent,” the Italian said. “To come back on the podium was so important.” The true highlight of the race came as the two Yamaha riders staged a brilliant duel with two laps remaining. Riding side by side, their bikes touched as they overtook each other at successive corners during the final lap. But Rossi, still suffering shoulder pains, had the final say. “It was funny,” the nine-time world champion said. “We had some overtaking. But you know, in the last lap ... to take a place on the podium, you have to never give up.” Stoner's victory, however, did not change Lorenzo's strong position in the overall championship standings. With only four races remaining Lorenzo can secure the season title with a solid showing in the Malaysian Grand Prix next weekend if second-ranked Dani Pedrosa misses the event. Pedrosa, the only racer with a chance of overtaking Lorenzo, pulled out of Motegi after crashing during practice on Friday, when he broke a collarbone into four pieces. He immediately flew home to Spain and underwent a successful operation Saturday, but it remained unclear exactly when he would be able to return to racing, his physician said in Barcelona. In other races at the Grand Prix, Toni Elias on a Moriwaki won the Moto2 category to extend his season championship lead. The Spaniard grabbed his seventh victory of the season, clocking 43min 50.930sec, followed by pole-starter Julian Simon on a Suter, who came in 0.315sec later. Czech rider Karel Abraham on an FTR earned his first podium finish, coming in third, off 9.839sec. In the 125cc race, Marc Marquez on a Derbi won, followed by Nicolas Terol and Bradley Smith, both on Aprilias. – Agence France