The 2021 IndyCar Champion Alex Palou has been testing for McLaren at the Hungaroring alongside Oscar Piastri.
The three-day test took place at the circuit which hosts the Hungarian Grand Prix, with both Palou and Piastri running in the team's 2021 chassis, the MCL35M.
Test and development driver Oliver Turvey will complete the test on Friday for the team.
Although Palou drives for McLaren's rivals Ganassi Racing in IndyCar, he is still part of their junior driver programme and is one of their official F1 reserve drivers.
The Spaniard had his F1 weekend debut during the United States GP at the Circuit of the Americas last year, which followed a handful of tests alongside Pato O'Ward throughout 2022.
Speaking on social media, Palou was upbeat about the test: "Had a blast driving the F1 car today in Budapest!"