The Aston Martin ended proceedings 0.230s clear of George Russell in second, with Max Verstappen only third fastest.
The start of the session was delayed by 10 minutes to fix loose bolts on drain covers in pit lane.
Soon after it got going, Valtteri Bottas lost the back end of his Sauber at Turn 1, spinning off the track in the process.
It was a low speed lose, and he was able to flick the car around and get going once more.
Conditions were far more representative of those expected in Qualifying and the race, with the sun having set.
The wind had also died down slightly, though it remained a headwind into the first corner.
In the early minutes, RB sent Daniel Ricciardo and Yuki Tsunoda out on a set of soft compound tyres.
They were the only cars on track on the red-walled rubber, the others opting for a mix of medium or hards.
Fernando Alonso was fastest after the opening 10 minutes, the Spaniard heading Verstappen, Leclerc, and Norris.
Logan Sargeant had a near miss when he arrived at full speed behind Lewis Hamilton, who had Carlos Sainz trailing him well off the pace.
It was an incident that caught the eye of officials who noted it before announcing it would be investigated post-session.
In the other Mercedes, George Russell complained of highspeed instability in the W15.
Russell was fourth fastest in Free Practice 1. He sat fifth fastest after 15 minutes of Free Practice 2 as he registered his complaints to the team.
After 20 minutes, Verstappen had risen to the top of the timesheets on medium rubber, heading Alonso by 0.017s with a best of 1:29.543s.
The Spaniard swapped to the soft tyres and promptly recorded a 1:28.827s.
Also on the softs, Verstappen improved by 0.2s on his previous effort to bank a 1:29.377s and sat only fifth fastest halfway through the 60-minute session.
Lando Norris was only eighth best after his qualifying simulation, the McLaren driver complaining of bottoming in the MCL38.
Oscar Piastri ran slightly off sequence and set his best lap a little later in the session but recorded a similar time – 1 1:29.774s just 0.016s away from his team-mate.
Another effort lap saw Verstappen improve to second best, still 0.331s off the pace.
It was a frenetic session on track with traffic, especially through the first sector, creating a number of eyebrow-raising moments.
As well as Hamilton, Alonso had one, too as Sainz moved off line to the left and Lance Stroll to the right as the two-time world champion stormed by both at full noise.
Russell then had a moment, when Tsunoda appeared to squeeze him as the RB cruised around the final corner. Even Sainz had to abort a lap when he encountered Norris.
With the qualifying simulations in the bad, the later third of the session was set aside for race runs. As a result, the order didn’t change.
Hamilton had a late slide through Turn 22 before reporting a loss of power in the Mercedes, limping back to the pits.
There were no such issues for Alonso who was fastest. Russell was second best, 0.2s away from the leading Aston Martin, with Verstappen third.
Piastri finished up 10th, faster than Norris by 0.15s, with Ricciardo just 19th but clearly running to a different programme.
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