SAO PAULO (Reuters) - Nico Rosberg took the fight to championship-leading Mercedes team mate Lewis Hamilton with the fastest laps in both Brazilian Grand Prix practice sessions on Friday while Fernando Alonso's Ferrari caught fire.
The German started the day with a best time of one minute 12.764 seconds on a cloudy morning at the Interlagos circuit and finished the afternoon with an effort of 1:12.123.
Hamilton, who has won the last five grands prix and is chasing his 11th victory in 18 races, was a close second in both sessions on a day overshadowed by news of the Marussia team's demise after they had previously gone into administration.
Rosberg desperately needs to win on Sunday, even if the championship cannot be decided before Abu Dhabi at the end of the month when double points are on offer, after Hamilton forged 24 points clear in the championship.
"That was a good day and we are very quick again at this circuit," Rosberg told reporters.
"The track has a new surface which made it quite tricky. It's smooth and not quite so bumpy as it has been in the past but the tyres were blistering because of the high temperatures and the new asphalt.
"That was a bit worrying but we are expecting it to be a bit cooler over the weekend."
Hamilton said he had not managed to put a good lap together but was otherwise unconcerned.
"It's different every time we come here and you never know what the weather is going to do. But that's what makes this such an exciting race," said the Briton.
Russian Daniil Kvyat, who steps up to Red Bull next season, was third fastest for Toro Rosso, but nearly a second slower than Rosberg, in the morning while Ferrari's Kimi Raikkonen filled that spot after lunch.
Raikkonen's team mate Fernando Alonso was one of three drivers to bring out the red flags in the afternoon when he pulled over with flames shooting out of the back of his car.
The Spaniard, who was fourth fastest in the first session, jumped out and ran to get an extinguisher before returning to put out the blaze.
"We knew the power unit had reached the end of its cycle, so there was a risk we wouldn't finish the second session, but this was part of the program we have been on for a few races now," said the Spaniard who will not be penalized.
Frenchman Jean-Eric Vergne, in a Toro Rosso, and Mexican Esteban Gutierrez in the Sauber, also halted the session when they stopped on the track.
Brazil's sole representative Felipe Massa in the Williams was fifth and sixth respectively.
Dutch teenager Max Verstappen continued to impress before his race debut next year, with the sixth fastest lap for Toro Rosso in morning practice before handing the car back to Vergne.
McLaren's Jenson Button, the winner in Brazil in 2012, failed to set a time in the first session after suffering electrical problems in a miserable start to his weekend and was then 16th in the afternoon.
Spaniard Daniel Juncadella, replacing Mexican Sergio Perez at Force India for the morning session, brought out the first red flags of the day when he crashed into the barriers with considerable damage to the car.
Perez was unable to set a lap in the afternoon as the team worked on repairs.
Editing by Tony Jimenez