A first lap containing spins, shunts and a pit-lane fireball – more incidents, in fact, than most entire races – set the scene for today's Brazilian grand prix, an absorbing contest in which the celebrations were shared by Mark Webber, winning for the second time this season in his Red Bull-Renault, and Jenson Button, whose fifth place brought him and the Brawn-Mercedes team the double of the 2009 world drivers' and constructors' championships.
Given the testing circumstances, Button's drive was the equal of the very best of the six victories he collected in the first half of the see-sawing season. After a catastrophic qualifying session he took his fate into his own hands and drove with controlled aggression. When the slightest mistake would have meant disaster, he executed a series of overtaking manoeuvres with measured authority.
At the start of the afternoon the permutations were almost endless. A podium finish would secure the title for Button but a poor tyre choice on Saturday reduced him to 14th place on the grid and gave hope to his team-mate Rubens Barrichello, starting from pole position in front of his home crowd. Sebastian Vettel, the championship outsider, needed both a victory and a bad day for both Brawn drivers, but was another Saturday casualty and started one place behind Button.
Within a lap much had changed. Adrian Sutil's Force India, starting from third on the grid, was overtaken by Kimi Raikkonen's Ferrari as the cars plunged through the dramatic downhill esses and then tangled with Jarno Trulli's Toyota at high speed, putting both cars out. The Italian veteran, believing he had been edged off the track, confronted the young German with a series of gestures suggesting that they might be meeting again to sort it out away from the public gaze. The stewards ruled that it had been a racing incident but fined Trulli $10,000 for refusing to leave the track and for the manner of his confrontion with Sutil.
Meanwhile Heikki Kovalainen had spun his McLaren halfway round the lap, forcing another tailender, Giancarlo Fisichella's Ferrari, on to the grass. Kovalainen dived into the pits for new tyres and left just ahead of Raikkonen, who had lost his front wing while trying to pass Webber. The McLaren driver, however, restarted with the fuel hose still attached (for which the team were fined $50,000), covering his fellow Finn's Ferrari in a film of petrol which ignited in a spectacular blaze that momentarily blinded Raikkonen but was quickly extinguished by the airflow as he accelerated away. "An interesting first lap, as usual here," Webber said, with dry understatement. At the end of it, with the safety car out, the Australian was tucked in behind Barrichello and ahead of Nico Rosberg's Williams and Robert Kubica's BMW-Sauber.
Profiting from the misfortunes of others and from his own success in staying out of other people's accidents, Button was already up to ninth position and preparing to go about the business of improving his prospects. Cool and decisive moves in the esses took him past Romain Grosjean's Renault and Kazuki Nakajima's Williams on successive laps but Kamui Kobayashi, a grand prix debutant replacing Timo Glock at the wheel of the second Toyota, proved a more troublesome obstacle.
For 18 laps Button sat behind the Japanese driver, observing his opponent's questionable racing etiquette before picking his moment to pass. "That guy is crazy," he said later. "He moves a lot in the braking zones, which makes it very difficult, as Nakajima found out." The other Japanese driver's attempt to overtake his compatriot ended in an expensive shower of carbon fibre, his Williams smashing itself against the barriers while the Toyota continued on its erratic way, eventually finishing 10th.
Now up to sixth place, Button was able to follow his strategy in relative peace, his position improved – and his title sealed – when Barrichello, having slipped to third behind Webber and Kubica during the first stops, suffered a puncture with eight laps to go. A third pit stop relegated the Brazilian to eighth place, continuing his run of appalling luck at his home circuit. Like Vettel, who finished an excellent fourth after a fighting drive, he saw his championship chances disappear.
The final place on the podium went to the McLaren of Lewis Hamilton, his drive from 17th place on the grid doing great credit to a man relinquishing his title but already making plans to mount a challenge to its new holder next year.
Red Bull driver Mark Webber won the FIA Formula One 2009 Grande Prêmio Petrobras do Brasil Saturday at Autódromo José Carlos Pace, São Paulo, Brazil. 

Interlagos (Autódromo José Carlos Pace)
Robert Kubica came in second for BMW Sauber, and Lewis Hamilton finished third for McLaren.

Webber's teammate Sebastian Vettel started from 15th place on the starting grid after he couldn't come up from the first qualification session, but finished 4th in front of his championship rival.

Brawn Grand Prix driver Jenson Button finished 5th to win his title. His team, representing the remnants of Honda Racing, also won the 2009 Constructors' championship after leading through the season.

The team's road to victory was not smooth — a scandal broke with the "double-decker diffuser" of the BGP001 car.  After the FIA declared them legal and other teams started to borrow the idea, Brawn sped up by collecting points on the way to the title.

Brawn GP, the winning constructor
Kimi Räikkönen (Ferrari) and Sébastien Buemi (Toro Rosso) dropped one place from the starting grid and finished behind Button.

Button's teammate and possible vice-champion Rubens Barrichello, who won pole position on his home soil after nearly three hours of a long rainy qualification session, had a tire puncture on the dying laps of the race and was forced to make an unscheduled third visit to his pit. He closed in the top eight.

This Brazil GP featured Japanese rookie driver, Kamui Kobayashi (Toyota), who replaced recovering Glock. In his first race this young driver qualified 11th and finished 10th in the race.

Adrian Sutil qualified 3rd for Force India, but was taken out by Jarno Trulli (Toyota) on the first lap.