Sao Paulo: Nico Rosberg kept championship-leading Mercedes team mate Lewis Hamilton off the top of the timesheets in first practice for the Brazilian Grand Prix on Friday.
On a cloudy morning at the Interlagos circuit, the German lapped with a best time of one minute 12.764 seconds with Hamilton second fastest and 0.221 slower.
Rosberg desperately needs to win Sunday`s race, the penultimate of the season, after Hamilton forged 24 points clear in the championship with five successive victories to take his season`s tally to 10.
The championship cannot be decided in Brazil, despite Hamilton`s advantage, because of the unprecedented and controversial decision to award double points in the final round in Abu Dhabi.
Russian Daniil Kvyat, who steps up to Red Bull next season, was third fastest for the Toro Rosso team but nearly a second slower than Rosberg.
Ferrari`s Fernando Alonso ended the session in fourth place, ahead of Brazil`s sole representative Felipe Massa in the Williams.
Dutch teenager Max Verstappen continued to impress before his race debut next year with the sixth fastest lap in the Toro Rosso that will be raced by Frenchman Jean-Eric Vergne on Sunday.
McLaren`s Jenson Button, a winner in Brazil in 2012, failed to set a time after suffering electrical problems in a miserable start to his weekend.
Spaniard Daniel Juncadella, replacing Mexican Sergio Perez for the morning session at Force India, crashed into the barriers with considerable damage to the car.