Carlos Sainz ended the opening morning of post-season Formula 1 testing as the fastest driver from Abu Dhabi.
Following his disappointing season-ending race from the Yas Marina Circuit, Sainz logged 69 laps behind the wheel of the SF-23, which delivered him a victory in Singapore earlier this year.
The Spaniard headed Sergio Perez in the Red Bull while Oscar Piastri was third as he closes out his rookie season for McLaren.
The session saw two red flags - one for a water leak between Turns 13 and 14 before George Russell stopped on the track with an issue.
Other notable names that were part of the test included Formula 3's Franco Colapinto, who drove the Williams FW45 as part of his role within the team's driver academy.
Japanese driver Ayumu Iwasa also made his F1 test debut, jumping behind the wheel of the AlphaTauri and setting 41 laps during the opening morning - the fewest of any driver.