Lewis Hamilton headed team-mate Valtteri Bottas as Mercedes finished one-two in first practice at the Brazilian Grand Prix.
Hamilton was 0.127 seconds ahead of the Finn, with Ferrari’s Kimi Raikkonen a further 0.415secs behind and 0.006secs ahead of Red Bull’s Max Verstappen.
Red Bull’s Daniel Ricciardo was fifth ahead of Ferrari’s Sebastian Vettel.
Williams’ Felipe Massa was seventh, ahead of McLaren’s Stoffel Vandoorne and Force India’s Esteban Ocon.
British 19-year-old George Russell, making his debut at a grand prix weekend with a run in first practice at Interlagos, was 12th quickest in the Force India, three places and 0.6secs off team-mate Esteban Ocon in a controlled and impressive debut.
Hamilton clinched the championship at the last race in Mexico, but has arrived in Brazil saying that he is determined to ensure he does not have the same post-title slump that he had the last time he clinched the championship early in 2015.
“There are two races to go,” Hamilton said on Thursday. “It is a better time than ever to apply even more pressure, just because you can.”
That remark was a reference to the implosion of Ferrari driver Sebastian Vettel’s title challenge in the last few races, from leading it after the Belgian Grandz Prix at the end of August, to losing it just six races later with two still to go.
On the evidence of first practice, Hamilton has a strong chance to continue his winning form – Mercedes appeared to be in a league of their own at this early stage.
Ricciardo already knows he is in for a difficult weekend as he has a grid penalty of 10 places for using too many engine parts this season, Renault having fitted a new MGU-H to replace the turbo hybrid recovery unit that failed on his car in Mexico.
Both Toro Rosso drivers also have 10-place engine penalties for taking new MGU-Hs and have had a torrid time on track.
Pierre Gasly managed only five laps before stopping with an engine problem but the Frenchman fared better than team-mate Brendon Hartley, who did only two laps before his Renault engine failed in a cloud of smoke.
It was a repeat of the problems Toro Rosso suffered in Mexico and team boss Franz Tost held his head in his hands on the pit wall in despair.