Works Mercedes Formula E driver Nyck de Vries topped the timesheet on the opening day of F1's post-season test in Abu Dhabi.
A selection of rookie and junior drivers blended in with F1 team's regular drivers as a young drivers' test ran parallel to Pirelli's 18-inch wheel development program that features mule cars supplied by all teams save for Williams.
De Vries jumped to the top of the timing screen in the session's final 30 minutes, setting the quickest time at 1m23.194s. The Dutch driver was over 1.3 seconds faster than second-placed charger Liam Lawson, running with AlphaTauri.
Freshly crowned FIA Formula 2 Champion Oscar Piastri completed the top three for Alpine, while IndyCar start Pato O'Ward was fourth for McLaren.
Thereafter followed Alfa Romeo rookie Guanyu Zhou and Red Bull junior Yuri Vips, who brought out the red flags following a crash at Turn 14 onboard his 2021-sepc RB16B.
Aston Martin sim driver Nick Yelloly was P7, with McLaren's Daniel Ricciardo leading the field of mule cars equipped with next year's 18-inch wheel.
Lance Stroll was ninth, with Ferrari junior rounding off the top ten at the wheel of the Scuderia's SF21.
Further back, Charles Leclerc lined up P11 with the Italian outfit's mule, just ahead of Alfa's Valtteri Bottas and Ferrari junior Antonio Fuoco.
AlphaTauri's Yuki Tsunoda in P14, Williams junior Logan Sargent, Alpine's Esteban Ocon preceded 2021 F1 world champion Max Verstappen and Mercedes' George Russell.
Haas' Mick Schumacher brought up the rear for Haas in the US outfit's mule car.