SUZUKA (AFP) - Germanys Sebastian Vettel became Formula Ones youngest back-to-back world champion on Sunday when he finished third in the Japanese Grand Prix behind Jenson Button and Fernando Alonso. The Red Bull driver, 24, who needed just one point to clinch the title, joins Juan Manuel Fangio, Ayrton Senna and Michael Schumacher as one of only nine drivers to successfully defend the title. He ran down the pit lane to celebrate with his mechanics after the race, which sealed the championship with four grands prix remaining following a dominant season with nine wins in 15 outings. Life for me, and I think all the drivers, doesnt get much better than this. Sunny days, a lot of fans, everyone excited to see what you do. I think that is what life is about, an emotional Vettel said. To wrap up the championship here, which has been the ultimate target this year, is difficult to put in words. Its more than fantastic. The German said he did not know quite how to react to his own achievement, adding: It does take some time to understand. At just 24 years and 98 days, Vettel outstrips fellow consecutive winners Alberto Ascari, Fangio, Jack Brabham, Alain Prost, Senna, Schumacher, Mika Hakkinen and Fernando Alonso as the youngest driver to achieve the feat. Buttons victory, which came after he passed Vettel in the second round of pit stops on lap 21, was his third of the season and the 12th of his career. The McLaren driver finished 1.1 seconds ahead of Spains Alonso of Ferrari, with Vettels third place easily enough to secure the world title. Australian Mark Webber was fourth for Red Bull, eight seconds adrift of Button, while Briton Lewis Hamilton of McLaren had another controversial race, clashing again with Felipe Massa of Ferrari en route to finishing fifth. Schumacher was sixth for Mercedes, briefly leading the race after the final round of pit stops, while Massa was seventh. Mexican Sergio Perez came through from 17th on the grid to take eighth for Sauber with a two-stop strategy, while German Nico Rosberg drove his Mercedes from second-last on the grid to finish 10th. Vettel didnt lead last years world championship until after the final race in Abu Dhabi, but this season he has never been headed in the standings. However Button, who took his fifth win for McLaren and his first in dry conditions since joining the team, said the victory showed Vettels competitors were closing the gap on dominant Red Bull. This circuit is very special to all of us, so to get a victory here in front of this Japanese crowd means a lot, Button said. This gives us a lot of motivation. To see three cars within a few seconds (at the finish) shows how competitive F1 is right now. He said it was very emotional to win on what was a fast and flowing circuit, and added that the feeling was almost like winning his first home Grand Prix. Button needed to win the final five races of the season and have Vettel not score a point to extend the championship to next weekends race in South Korea, and he made a strong start, shaping up to pass Vettel into the first corner. But the German defended robustly, prompting Button to tell his McLaren team over the radio that hes got to get a penalty for that. But stewards decided to take no further action. Vettel led the race through the first set of pit stops, but after re-passing Hamilton on lap eight, Button narrowed the gap and finally passed the German as he returned to the track following his tyre-change on lap 21. On the next lap, Hamilton and Massa clashed at the final chicane, with a piece of front wing from Massas car left in the middle of the circuit, prompting a three-lap safety car period to remove the debris. The incident was investigated, but no action was taken. The clash follows a series of bad-tempered incidents this year between the pair, with Hamilton running into the back of Massa in the most recent race in Singapore.