Arvid Lindblad led the way for Racing Bulls just after the opening hour of Formula 1's pre-season test in Bahrain on Wednesday.
With all 11 teams at the track for the first time this year, after Williams missed the behind-closed-doors Barcelona test entirely, this week is also the first time that the cars have run in public.
F1 rookie Lindblad wasted no time in getting down to business early on, completing a lengthy stint on soft tyres in the first hour to become the first driver to get over the 20-lap barrier.
Then shortly after the first hour of running, the British driver delivered a lap of 1m37.945s that put him at the top of the timesheets - just edging out McLaren's Oscar Piastri.
Lindblad's pace and long stints, allied to Red Bull's Max Verstappen setting the third-best time, continues an impressive start for the team's new power unit that has impressed with both its pace and reliability.
Carlos Sainz was fourth fastest early on as he was giving Williams its first proper test day, with the team having only completed two filming days so far after missing Barcelona because its car build was late.
A number of drivers found themselves catching some wild moments as they got to grips with the 2026 cars around the Sakhir track during Wednesday's morning running.
Ferrari's Lewis Hamilton had a small off as he ran across the asphalt runoff at the double-left Turns 9 and 10, with Franco Colapinto in the Alpine, Lance Stroll in the Aston Martin, and Valtteri Bottas in the Cadillac also having moments in the same sequence.
Colapinto later brought out the first red flag of the test when he stopped between Turns 7 and 8.
Stroll only completed a handful of installation laps in the first hour but added to his tally later on as Aston Martin starts to understand more about its AMR26.
Gabriel Bortoleto gave some striking-looking sidepods a debut outing on the Audi, as the squad brought some upgrades to its R26 challenger.
