Lando Norris led the way in a disrupted first practice at the Azerbaijan Grand Prix as title rival Oscar Piastri was hampered by an engine issue.
Championship leader Piastri, who enters the weekend 31 points clear of Norris with eight rounds remaining, was immediately told to return to the garage after starting his session.
The Australian jumped out of the car and McLaren confirmed they were attempting to fix a power unit issue.
Piastri was fortunate to not miss a huge amount of track action, as Friday’s opening running was delayed by 20 minutes due to an issue with the kerbs at the final corner.
In bizarre scenes, a marshal was seen jumping up and down on the kerb and there were only 20 minutes left of the session by the time the problem was fixed.
By that time McLaren had remedied Piastri’s issue and the teams dashed to put in some laps.
Norris set the pace early on and was immediately the fastest man on track again, finishing the session 0.310 seconds clear of Piastri.
Piastri was unable to find the same pace as his teammate around the challenging street circuit but, despite flirting with the wall, put in a lap late on to close the gap.
Charles Leclerc was third for Ferrari ahead of Mercedes’ George Russell, who was back in the car after missing media day on Thursday through illness.
Monza winner Max Verstappen locked up into the run-off area at turn 15 and ended the session 1.086 seconds behind Norris in seventh.
Lewis Hamilton endured a difficult moment late in the session as he banged the wall on the inside of turn five, suffering a puncture and front wing damage.
The struggling Ferrari driver ended the session down in 13th, 1.383 seconds off the pace.
Second practice gets under way at 1600 local time (1300 BST).
