Valentino Rossi won his ninth world championship with one round of the 2009 season to spare, after a third place finish at a wet Sepang in Malaysia on Sunday.

The 30-year-old, who has now won seven world championships in the premier 500cc/MotoGP class, had taken the 2009 title lead with his first win of the season at round three in Jerez.

Fiat Yamaha team-mate Jorge Lorenzo and Ducati's Casey Stoner then fought back, and all three were level at the top of world championship standings after round six in Catalunya.

The next five rounds proved crucial, with Stoner falling victim to mystery fatigue problems while Lorenzo crashed out at both Donington Park and Brno.

Rossi won three of those five races to build his title lead to a peak of 50 points after the Czech Republic, but instantly lost half that advantage - and threw Lorenzo a championship lifeline - when he crashed out of the following Indianapolis Grand Prix.

The see-saw continued with a Rossi victory at Misano and then a Lorenzo win at Estoril - when Rossi was only fourth, dropping his title advantage to 18 points.

The pressure was on for Phillip Island but Lorenzo cracked first, making a mistake into turn one and crashing out, effectively wrecking his hopes of taking the title down to the final round in Valencia.

38 points clear heading into Sepang, Rossi only needed to be 25 points ahead of Lorenzo to wrap up the title - a feat he easily achieved after converting a record 58th pole into third place in the rain-delayed race, one place in front of Lorenzo.

"Nine world championships is a great achievement, I'm so happy!" said Rossi. "I would need one hour to thank everyone! Starting with everyone at Yamaha - Furusawa-san, Lin Jarvis, Davide Brivio and all my guys, especially Jeremy. I couldn't have done it without Jeremy and he is like my motorcycle father!

"I also have to thank my family and friends - Stefania, Graziano, Uccio, many! All the team, Yamaha and Bridgestone; together we've done a great, great job and it's always a huge enjoyment to ride and work with these people.

"In order to stay at this level through a whole season you have to be calm and have the right people around you and this is what I have. We've stayed concentrated and focused even in the bad moments, so we can congratulate ourselves with this ninth title."

Rossi suffered a scare at the start of the race when he ran wide whilst trying to outbrake Dani Pedrosa into turn one and had plummeted to tenth - behind Lorenzo, who had started from the back of the grid - by the end of a soaking first lap.

The #46 then shadowed his team-mate up the order, before taking fourth from the young Spaniard on lap eight of 21. That became third position when Andrea Dovizioso crashed out on lap 15, allowing Rossi to reach his target of celebrating championship victory from the podium.

"Without the rain it could have been a brilliant race, with the four top riders fighting together, but the rain changed it," said Rossi of the weather. "It was scary for everyone because all the work we'd done was useless and we were riding 'blind' with the setting.

"I made a good start but I made a mistake at the first corner in braking, it felt like I was braking for one year and I went wide!" he smiled. "Of course I wanted to win but after the first corner it was difficult with Casey so strong so I went for the podium. I really enjoyed the race and I think it was great to watch.

"After Dovizioso unfortunately crashed I tried to go with Dani but then he started to push and I already had the podium, so I decided to take it a bit easier. I was happy to risk a little for the podium, but it wasn't sensible to keep taking risks for second when the championship was safe."

As has come to be expected, Rossi and his fan club had a special celebration waiting for the #46 after the race - who was handed a t-shirt and helmet with the number 9 on and the words 'old hens make the best soup'. A live hen, complete with Rossi livery, was also on hand, as were nine eggs!

"The t-shirt and the celebration is called the 'Gallina Vecchia!" In Italian we say that the old chicken makes good soup, but it's no use for laying eggs. I am old now, 30, but this old hen has made another egg today and now we have nine!" he said. "As usual I thought it up at home in Tavullia, together with my fan club, and we had great fun designing the t-shirt and the helmet."

2009 was unique for Rossi, since it marked the first time since joining the premier-class that his team-mate had also been his main title rival.

"It's been a great season, for sure one of the hardest at times," reflected Rossi. "It's been harder than last year, when we won after two difficult years, but we've had some troubles this year at times and I have had a very hard rival in my team-mate Lorenzo. He has pushed me to new levels and I think it's been a great duel to the end.

"There have been some bad moments, like Portugal when we weren't at 100%, but we have worked well. Lorenzo has done a great job to put this pressure on us so I have to say well done to him."

"Every year is special but this year was very interesting because we realised from the start of the season that our strongest rival was in our garage," confirmed Rossi's team manager Davide Brivio. "It hasn't been easy but it's been a fascinating season for everyone."

Rossi has won six of the 16 races so far this season, compared with four victories for Lorenzo, four for Casey Stoner - who dominated Sunday's race - and one each for Repsol Honda riders Pedrosa and Dovizioso.

Crucially, Rossi failed to score points only twice (Le Mans and Indianapolis) compared with four times for Lorenzo.

"This season we've had a mono-tyre rule but we have still improved the lap record in many laps and this shows that we've all been on the limit all season," commenedt Rossi. "This is why we've all made mistakes; this is to be expected when you have four riders fighting together.

"The best moment of the season for me, the best emotion, was the last pass in the last corner at Barcelona," said Rossi, who snatched home victory from Lorenzo in Catalunya. "This was the most exciting moment of the championship for me, one of the best for many years I think! The worst moment was probably the stupid error and crash in Indianapolis, but this led to the perfect win in Misano in front of all the fans so in the end it was okay!"

Seven MotoGP titles is just one less than the record of Giacomo Agostini, while nine world championships in all classes puts Rossi equal third alongside Mike Hailwood and Carlo Ubbiali - and behind only Angel Nieto (13) and Agostini (15) .

"I still feel just as motivated as ever," insisted Rossi. "I still have a great passion to ride better and better, to be on my bike and to win. I enjoy always trying to improve and to work with my team to do this. I am 30 but I still feel great emotion and great satisfaction from success.

"My passion for motorcycles is what keeps me enjoying every race and helps me to keep pushing even though I am the oldest of these first top guys. I have to train harder and work harder to stay focused now, but I still enjoy the challenge as much as ever.

"I think next year will be very, very hard. We're all on the same bikes and I think it will be between me, Lorenzo, Stoner and Pedrosa again. On Tuesday in Valencia we will try the new model and I am looking forward to working on the new M1, but I have the greatest rival in my team so it won't be easy!

"Every championship is special for different reasons, it's unforgettable every time and this day is no different. I'm world champion once again and now I want to go and party!" Rossi concluded.

"We have to give huge congratulations to Valentino because this year we've seen him work harder than ever, and when the level goes up he puts even more effort in and this means that we, too, have all had to work even harder to keep up with him!" added Brivio.

Rossi's nine titles are split four with Yamaha, three with Honda and two with Aprilia.

Fiat Yamaha has won the 2009 Teams' title while Yamaha is assured of the Constructers' crown providing M1 riders do not break the new engine limit rules.

The final round of the 2009 MotoGP season will be held at Valencia on November 8.