Lewis Hamilton, with four world championship stars now painted on his race helmet, smashed the Interlagos track record as Mercedes dominated the opening Brazilian Grand Prix practice.
Showing no sign of letting up despite clinching his fourth world title in Mexico at the end of October, Hamilton lapped the anti-clockwise track with a best time of 1 minute, 09.202 seconds.
Hamilton returned to the track on Friday afternoon to post a best lap of 1:09.515 seconds to edge out teammate Vallteri Bottas by just five hundredths of a second on a strong day for Mercedes.
"There are two races to go. It is a better time than ever to apply even more pressure, just because you can," Hamilton said on Thursday.
Bottas, who is bidding to end the season as runner-up to the Briton, was also second fastest in the morning in 1:09.329 while Australia's Daniel Ricciardo was fifth but faces a grid penalty.
The previous track record of 1:09.822 was set by Brazilian Rubens Barrichello in 2004 qualifying for Ferrari.
Hamilton, who also accused Renault's Nico Hulkenberg over the radio of dangerous driving in forcing him wide onto the run-off, was half a second faster than Ferrari's Kimi Raikkonen.
The Finn was the best of the non-Mercedes rest, with Red Bull's Dutch 20-year-old Max Verstappen fourth on a sunny morning in Sao Paulo.
Ferrari's Sebastian Vettel, who had an early spin, was sixth.
Mercedes have clinched the constructors' championship for a fourth successive year and have said they will use practice at the last two races to experiment with processes and parts for 2018.
With none of the top four teams able to improve their placings or in any danger of dropping down the order, others were also turning their thoughts to next year.
"Obviously, both cars have got bits that they (the engineers) are having a look at for future events," said Red Bull boss Christian Horner, whose team have won two of the last four races with Verstappen.
"These sessions are so valuable now. They are the last opportunities this year to try a few things out for future car development."
Red Bull's Ricciardo will have a drop of at least 10 grid places due to power unit changes while Toro Rosso's Brendon Hartley and Pierre Gasly will also pick up engine penalties.
