"Looking at us, looking at our car, I think we should be in good shape for the next two races," Vettel said. "Brazil is a track we know, Abu Dhabi is unknown for everyone, so we don't know, but I think independent from the circuit type, we have always been competitive."

Vettel finished fourth in last year's Brazilian Grand Prix.

Button began this season by winning six of the first races, but has not finished better than fifth since his victory in the June 7 Turkish Grand Prix.

"It's an important race for me and for the team in terms of the championships, and we will be working hard to get the best results possible from the weekend," said Button, who finished 13th in the 2008 Brazilian GP while driving for the now-defunct Honda Racing F1 team. "It's going to be a challenge, but one that we are all looking forward to."

Button will clinch the title in Brazil if he finishes third or better, or Vettel has a result lower than second and Barrichello, who races in front of his home crowd, finishes worse than fourth. Button's best finish in Brazil is third (2006).

Barrichello trails Button by 14 points. The Brazilian finished seventh in Japan and gained one point on Button.

"The Brazilian Grand Prix is always a special weekend for me, and I am very proud of my home race," Barrichello said. "The circuit has become almost like a second home to me over the years, but it still retains a real sense of challenge. Our car should suit the layout of the track this year, and you really need to have full confidence in your set-up to maximize the quick corners, the tight infield section and the bumpy surface."

Barrichello's best finish at his home track came in 2005 when he posted a third-place result. He finished 15th there last year.

For the last two years, the F1 world championship was decided on the final lap in the season-ending Brazilian GP. After losing the title by one point to Kimi Raikkonen in 2007, Lewis Hamilton captured last year's championship with a come-from-behind fifth-place finish.

Hamilton came to South America with a seven-point lead over Brazilian and Ferrari rival Felipe Massa. The McLaren driver was on the verge of losing the title on the final lap. Massa took the checkered flag by a sizeable margin, while Hamilton was running sixth. He passed Toyota's Timo Glock for fifth as he entered the last corner. Hamilton ended up winning the championship by a single point over Massa.

The Brazilian GP is this year's penultimate race, with the November 1 inaugural event in Abu Dhabi concluding the season. Next year's season-finale will move back to Brazil.