Max Verstapp led Red Bull to the first Abu Dhabi Grand Prix session.
The Dutchman, Formula One at the end of the season, was 0.454 seconds faster than Daniel Ricciardo in his last team match.
The drivers of Mercedes Valtteri Bottas and Lewis Hamilton were third and fourth, but used harder tires than Red Bull.
Ferrari, who spent time testing parts for 2019, was seventh and eighth, Kimi Raikkonen before Sebastian Vettel.
The Red Bull drivers were the only ones in the leading teams that managed to run a second series of the fastest hyper-soft tires that are fast for a lap but quickly lose grip for a longer period.
The Mercedes and Ferrari have managed to deal with the hyper-soft early, but then switched to more difficult tires, with Bottas setting their best time for super soft and Hamilton for ultra soft.
Hamilton, who won the championship two races in Mexico, does not seem so pleased with the performance of his car, saying during the meeting in the middle of the radio: "It's a pretty unfortunate car right now."
Bottas also ran two times when dealing with harder tires.
Hamilton works on Friday on the engine he used in the last race in Brazil, and at that moment the team felt within a lap.
Mercedes said the problems were with the variable valve system and that the settings were changed during the race to "keep the risk of failure / maximizing efficiency."
Mercedes say they have "made hardware changes outside the sealed perimeter and we are driving this engine today."
Mercedes will analyze the engine at the end of Friday's run. If this is not the case, they are faced with choosing between one who has already done seven weekends – and therefore will be over his planned life – or a new engine.
Elsewhere, Marcus Ericsson of Sauber had a turn in Tour 1, defeating his front wing in a light stroke with barriers in what would have been his last race before moving to Indycars next season.
And Fernando Alonso, whose successful career ends this weekend, extends in the penultimate corner and finishes the 19th session the fastest.
Alonso can still test McLaren 2020 next season, team boss Zack Brown said on Friday, but the Spaniard said his intention is not to come back.
Alonso said, "Right now, it's hard to think of coming back, but the door is not closed. The first reason is that I do not know how I feel next year, I've been doing it all my life.
"Perhaps next year, by April or May, I'm desperate on the couch to know that maybe I'll find a way to get back somehow, but that's not the original idea, but rather me. for each particular or the line or something that should happen, it's more like how I feel in the middle of next year. "
Alonso will compete in the Indianapolis 500 with McLaren, and will finish his work in the Toyota endurance world season with 2018-1919, and said he would do other races.
Meanwhile, there is a dispute between Haas and Force India.
Haas has filed a protest stating that Force India is competing with a car that they have not designed, which is contrary to the rules.
It is rooted in the collapse of Force India in the summer. The team was revived by the sale of their property to Canadian businessman Lawrence Starch and allowed him to return again as a new team.
But Haas immediately objected to the new entity being able to retain its prize by saying that if a new team can win a specific portion of the prize pool immediately, Haas should have a right to do so, not to impose meet a rule that teams can win this tranche after completing the top 10 in two of the previous three seasons.
Their complaints were ignored by the FIA and F1, and this protest is Haas's latest attempt to compensate.