Max Verstappen Red Bull Racing RB19.05.2023 World Championship. AP
Defending double world champion and series leader Verstappen clocked a fastest lap in one minute 12.776 seconds to outpace Perez by 0.073s before the session was halted four minutes prematurely when seven-time champion Hamilton crashed his revamped Mercedes.
He was unhurt and climbed from his car, apologising to the team having been on a fast lap.
Lance Stroll was third for Aston Martin ahead of Carlos Sainz of Ferrari and Lando Norris of McLaren in a closely-contested hour during which many of the drivers brushed, or hit, the barriers of the Mediterranean street circuit.
Pierre Gasly was sixth for Alpine ahead of Charles Leclerc in the second Ferrari, Hamilton, who was also fined for speeding in the pitlane in an eventful hour, Esteban Ocon in the second Alpine and Alfa Romeo's Valtteri Bottas.
The session was run in perfect conditions, blue skies and warm sunshine producing an air temperature of 27 degrees, with the track at 44. The streets and stands were packed with fans.
After a lifeless minute, Alonso was first out with Stroll and the two Alpha Tauris, the rest following in a leisurely manner. Ocon briefly lost power in the tunnel, where he almost stopped, but was saved by a system re-set.
Perez was first to set a fast time for Red Bull in 1:15.641 as the drivers tested the conditions before Norris went top for McLaren, followed by Verstappen in 1:13.794 and then to the delight of many Spaniards in attendance, Alonso who went clear by 0.097 seconds.
- 'No control' -
Mercedes delayed their entry by more than 20 minutes before Russell and Hamilton joined the fray, the Briton logging his first lap after 25 minutes.
By the half hour mark, Red Bull were back in control, trading fastest laps, with Verstappen edging clear of Perez and Leclerc who was struggling with his Ferrari.
"We need to change the car," said the Monegasque. "I have no control."
He reported it was "bottoming like crazy" through the Swimming Pool complex where team-mate Sainz had crashed on Friday.
With 25 minutes to go, it was Verstappen in 1:12.776, Perez and Sainz ahead of Leclerc, Hamilton and Alonso.
Proof that they were all pushing hard came with Verstappen brushing a wall and Russell, in seventh, doing the same in the final sector.
"A hefty hit of the wall," the Briton told the team as he pitted for repairs.
The order was revised when Stroll claimed third ahead of Sainz as the teams switched to fresh soft tyres for a final flurry, anticipating the decisive qualifying session to run later Saturday.
After a lull, the circuit was as crowded as the narrow shopping streets around the harbour as Alonso and Verstappen were slowed by rivals before Kevin Magnussen instigated yellow flags as he went off into the escape road at Sainte Devote.
After recovering, he stopped again at Portier and a Virtual Safety Car was deployed.
As soon as his Haas was cleared away, Hamilton hit the barriers at Mirabeau, ramming his left front wheel into railings. The session was red-flagged to a halt, with four minutes remaining.
He climbed from his car unhurt to make his long trek back to the pits as it was confirmed that the session would not resume.
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