George Russell holds the advantage going into Mexican Grand Prix Formula 1 qualifying after topping the third and final practice session.
The Mercedes driver edged out teammate Lewis Hamilton at the Autodromo Hermanos Rodriguez by 0.144s, with Max Verstappen suffering a scrappy session on his way to third with Charles Leclerc in fourth for Ferrari.
A 1:18.399s effort was good enough for Russell to secure top spot heading into qualifying, the second session he topped after FP2 on Friday afternoon.
Advantage Mercedes heading into qualifying
Russell was immediately on the pace in the W13, initially posting a 1:19.405s on the red-walled Soft tyres, nearly half a second clear of Red Bull's home favourite Sergio Perez.
This was before Verstappen emerged for his first flying lap of the session, and customarily went P1, but just one tenth of a second clear of Russell's effort.
With 22 minutes of the 60-minute session left on the clock, Russell and Hamilton emerged on fresh rubber for new attacks - the elder Briton having been about one second down due to mistakes and errors on his previous quickest lap.
Russell pumped in the 1:18.399s time to go 0.144s faster than Hamilton's 1:18.543s effort, having found about 0.7s on the new tyres.
Verstappen tried to respond, but abandoned his effort following a lock up at Turn 4.
He did whittle Russell's advantage down to 0.477s, but could not improve any further as Mercedes secured their first one-two of any session this season.
Leclerc was 0.724s down on Russell's time, with Perez, FP1 'winner' Carlos Sainz, Lando Norris and Valtteri Bottas all within one second of the benchmark time.
Yuki Tsunoda was ninth for AlphaTauri, with Alex Albon impressing once again with tenth place in the Williams.
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Struggles for Ricciardo and Vettel
Esteban Ocon clocked in the 11th fastest time in the #31 with Zhou Guanyu being the meat in an Alpine sandwich with Fernando Alonso 13th.
Daniel Ricciardo was 1.740s off the pace in the second McLaren and classified 14th, but was nearly 0.8s down on Norris, with Pierre Gasly in 15th - the final driver within two seconds of Russell.
Lance Stroll copped a pit-lane speeding penalty on his 24th birthday and was the lead Aston Martin in 16th, with Haas' Mick Schumacher causing a brief yellow flag after spinning on his way to 17th.
Nicholas Latifi was 18th for Williams, as Sebastian Vettel described his Aston Martin as "shocking" on his way to 19th.
The only driver to exceed the 1:21 mark was Kevin Magnussen in 20th, with a 1:21.271 being his best effort as he carries a five-place gird penalty into qualifying for new engine parts.
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