Oscar Piastri led a McLaren one-two in final practice for a season-ending Abu Dhabi Grand Prix that could crown the team Formula One constructors' world champions for the first time since 1998.
The Australian put down a best time of one minute 23.433 seconds, 0.193 quicker than teammate Lando Norris who was fastest on Friday in another one-two.
Seven times world champion Lewis Hamilton lapped third fastest, 0.390 off the pace, in his last practice session for Mercedes before moving to Ferrari next year.
Red Bull's Max Verstappen, his fourth title secured in Las Vegas last month, was fourth quickest but 0.411 slower than Piastri.
Ferrari's Carlos Sainz was fifth and teammate Charles Leclerc, who has a 10 place grid penalty for Sunday's race, only ninth.
"We are nowhere. Nowhere," said Leclerc over the radio.
Mercedes' George Russell was sixth, ahead of Haas pair Nico Hulkenberg and Kevin Magnussen. Red Bull's Sergio Perez completed the top 10.
McLaren are 21 points clear of Ferrari with 44 remaining to be won on Sunday, when conditions will be cooler with the start much later than practice.
"I think we’re really starting to get a picture of the situation out there. McLaren are in a league of their own and then it’s close behind," Mercedes' retired 2016 champion Nico Rosberg told Sky Sports television.
"Lewis has a great chance to finish on a high here, at the moment."
Australian Jack Doohan, making his race debut for Alpine, was a respectable 14th with team mate Pierre Gasly 13th and only 0.026 quicker.