Red Bull set the pace in the first practice session for the Brazilian Grand Prix, with Sebastian Vettel leading teammate Mark Webber with the fastest times.
Vettel clocked 1 minute, 12.328 seconds at the 4.3-kilometer (2.6-mile) Interlagos track, 0.482 ahead of Webber and 0.517 in front of Lewis Hamilton of McLaren. Hamilton teammate Jenson Button was fourth, 0.939 behind Vettel.
Leader Fernando Alonso of Ferrari was only the 13th fastest and failed to finish the session because of an engine failure as time was about to expire.
Five drivers remain in contention for the title — Alonso, Webber, Hamilton, Vettel and Button. Alonso has an 11-point lead over Webber and can clinch his third F1 title at the Brazilian GP. The season-finale is on 14 November in Abu Dhabi.
Alonso slowed down after exiting the first set of corners, stopping his Ferrari at the beginning of the backstraight and leaving the car. He was using an older engine and Ferrari said it was expecting to make a change in his car for the rest of the weekend. The team has been trying to save engines because Alonso was already on his eighth unit this season.
His best time was 1.918 seconds slower than Vettel's.
Ferrari driver Felipe Massa also struggled and was only the 14th fastest in front of his home crowd, nearly two seconds off the fastest time.
The morning session was uneventful until the final minutes, with drivers staying on the track under clear skies in Sao Paulo.
Toro Rosso driver Jaime Alguersuari was one of the few going off line but was able return to the track. Renault driver Vitaly Petrov skidded off the track and crashed into the tire barriers outside Turn 6 near the end, and later Sauber driver Kamui Kobayashi almost collided after going off on the same turn.
Robert Kubica of Renault rounded out the top five in the first session, 1.042 behind Vettel's time. Nico Rosberg of Mercedes was sixth, Rubens Barrichello of Williams was seventh and seven-time world champion Michael Schumacher of Mercedes was eighth.
Alonso can lift the trophy if he wins Sunday's race and Webber finishes fifth or worse. The Spaniard can also clinch the title if he finishes second and Webber places eighth or worse, Hamilton is fourth or worse, and Vettel is second or worse.
It was at Interlagos that Alonso won his first two titles, in 2005 and '06, with Renault. He is debuting with Ferrari after a brief stint with McLaren and two seasons with Renault before replacing Kimi Raikkonen in the Italian squad.
The Red Bulls have dominated nearly in every track this season but failed to capitalize on their chances after driver mistakes and mechanical failures.
Vettel has been on pole position nine times but won only three races, while Webber started up front five times and won four races.
Meanwhile a Brazilian prosecutor is warning Felipe Massa that he can be arrested and sentenced to up to six years in prison if he takes team orders to help Ferrari teammate Fernando Alonso win the F1title.
Massa could be charged with fraud if he allows Alonso to pass him or if he does anything else that would somehow alter the result of tomorrow’s race in Interlagos, according to prosecutor Paulo Castilho, known for taking up sports causes in Brazil.
“Massa or any other driver who does anything to fraud the result of the race can be arrested and formally charged,” he told The Associated Press on Thursday. “It doesn’t mean that it will happen, it will be up to the local authority in charge of the event to decide whether the law has been broken.”
The law mentioned by Castilho says that it’s a crime to “fraud by any means, or contribute to fraud, in any way, the result of a sporting event.”
Massa arrived at the Brazilian Grand Prix saying he would give way to his teammate if needed tomorrow, just like he did while leading the German GP in July so Alonso could earn more points in the race for the title.