Fernando Alonso topped the times for Aston Martin on Thursday evening ahead of George Russell and Max Verstappen in a busy floodlit second practice at the Saudi Arabian Grand Prix.
The two-time world champion clocked a best lap in one minute and 28.827sec to finish two-tenths and three-tenths respectively ahead of the Mercedes and Red Bull drivers.
Defending three-time champion Verstappen was fastest for spells in the session, but had no answer to Alonso's best lap in a wind-affected session.
Ferrari's Charles Leclerc was fourth ahead of Sergio Perez in the second Red Bull, Lance Stroll in the other Aston Martin and Carlos Sainz in the second Ferrari.
Seven-time champion Lewis Hamilton was eighth for Mercedes ahead of Pierre Gasly of Alpine and Oscar Piastri of McLaren.
After a 10-minute delay for repairs to loose drain covers in the pitlane, the session made a late start in cooling conditions after a hot day at the Jeddah Corniche Circuit.
McLaren led the way with Piastri ahead of Lando Norris (12th) as the lights went green.
Verstappen, winner of last week's season-opener in Bahrain, was soon on top, but Red Bull team-mate Perez responded to take the initiative before the much-improved Alonso leapt to the top for Aston Martin in 1:29.846.
After 12 minutes of action, Logan Sargeant had to move swiftly to avoid Hamilton, who was running slowly in the middle of the track, and Sainz. The stewards noted the incident.
Hamilton said he was avoiding Sainz and did not know another driver, on a fast lap, was behind him. The stewards chose to investigate after the session.
At this stage, most cars were running on mediums as Verstappen returned to outpace Alonso in 1:29.543, by 0.017.
It was clear that Red Bull were not enjoying a luxurious advantage and Alonso responded, surging to the top again by seven-tenths in 1:28.127 on soft tyres.
Verstappen and Leclerc improved their times, but only to second and third respectively, three-tenths adrift.
Further examples of drivers lapping slowly and endangering others saw both Russell and then Alonso cursing.
"A mess, it's so dangerous," said the Spaniard before Russell took second spot behind him, two-tenths behind.
With 15 minutes remaining, most chose to switch to race simulation runs with more fuel and hard compound tyres.
Many teams brought upgrades with them. Ferrari taking their 2023 rear wing in a bid to capitalise on their straight-line speed at the second-fastest circuit on the calendar.
Verstappen had shut out the noise surrounding his Red Bull team and boss Christian Horner to clock the fastest lap in opening practice earlier.
The latest twist in the Horner saga came ahead of FP1 when his accuser was suspended on full pay by Red Bull. Horner was cleared last week of any inappropriate behaviour levelled at him by the female colleague after an internal investigation.
AFP