(Reuters) - Spain's Dani Pedrosa claimed the 50th Grand Prix win of his career on Sunday, taking victory in the Japanese MotoGP as runner-up Valentino Rossi extended his lead in the championship standings.
Pedrosa, who almost quit the sport earlier this year because of an arm problem that needed surgery, grabbed the lead seven laps from the end of a wet race at the Twin Ring circuit in Motegi.
He surged clear of his rivals to win for the first time this season and the 50th of his career, which began in the 125cc class in 2001.
Rossi finished second while his Yamaha team mate and championship rival Jorge Lorenzo faded to third after leading for most of the race until he had dropped back when having tire problems.
"It's a real pity because today if the track didn't dry I would have won," Lorenzo of Spain said.
"There was a dry line and I couldn't follow them. I just had to survive.
"Now there is only one target and that is to win the three races. Let's see if we can do it."
Rossi now leads Lorenzo by 18 points in the standings with a maximum of 75 available from the remaining three rounds, in Australia, Malaysia and Valencia.
"It was a very long race. It was very easy to make a mistake," the Italian said.
"At this moment I need to take points. After Jorge left our pace was the same. When it got dry it was difficult to control the bike and I saw Jorge slowing.
"It's a good result for the championship."
Pedrosa had not won a MotoGP race since the Czech Grand Prix in August 2014 and missed three of the season's first four races due to the arm surgery.
The 30-year-old has suffered from a problem common among motorcycle racers when pressure builds up in the forearm and causes intense pain, making riding a bike difficult when the muscle becomes too big for the 'sack' that it sits in.
Sunday's race was delayed by heavy morning rain in Japan which forced organizers to shorten the Moto2 and Moto3 races but Lorenzo was all smiles at the end of a long day.
"It was not like I expected. At the beginning I had no good feeling with the rear and couldn't go fast," he said.
"I kept my rhythm while the others burned their tire. At the end my pace was faster and I'm really happy."
Johann Zarco celebrated his first Moto2 title by winning his seventh race of the season.
The Frenchman was already assured of winning the championship when Tito Rabat, the only other rider with any mathematical chance of overtaking him, withdrew from Motegi on Friday because of injury.
The race was cut to 15 laps because of the foul weather. After a slow start from pole, Zarco took the lead on the seventh lap and raced away to win.
Jonas Folger, a two-time winner this season, held on for second ahead of his fellow German Sandro Cortese, who claimed his first podium finish this year.
Italy's Niccolo Antonelli won the Moto3 race, which was reduced from 20 to 13 laps, while Britain's Danny Kent extended his championship lead to 56 points.
Antonelli made a flying start on his Honda and led all the way, capturing his second race win this year.
Miguel Oliveira finished second and Jorge Navarro third while Kent was sixth but still managed to stretch his lead by finishing ahead of his nearest title rival, Enea Bastianini.
Reporting by Julian Linden in Singapore; editing by Amlan Chakraborty