George Russell led Formula 1 teammate Lewis Hamilton in a Mercedes one-two in the second wet practice session for the Japanese Grand Prix.
The second session was extended to 90 minutes as it was planned to be a test session for dry weather Pirelli 2023 tyres, but the constant rain meant it was shelved until the United States.
Despite this, the session remained at the extended length, with Russell's 1m:41.935s effort good enough to secure P1.
Hamilton was about a quarter of a second down, with Max Verstappen nearly one second down as Red Bull struggled with overheating tyres at Suzuka.
Fernando Alonso, who topped FP1 was fifth, while Mick Schumacher did not take part following his crash at the end of the first session requiring a chassis change by Haas.
Mercedes on the pace
After the initial laps on the full wet tyres, Russell declared the track ready for Inters and pumped in a 1m:46.891s effort to leapfrog wet-shod Hamilton for P1.
The seven-time champion then came in for a change to the green-walled rubber and his 1m:44.298s took him P1, just 0.240s clear of the #63 Mercedes after Russell had shaved about two seconds off his own time.
The two then traded fastest laps with brief interloper Verstappen, as Russell worked down to a 1m:41.935s.
This stood as the fastest time of the session, about 12 seconds off simulated dry times, with Hamilton on a 1m:41.170s - some 0.235s behind the sister car.
Mercedes were able to keep heat in their tyres, something they struggled with, as Verstappen complained of overheating on his way to a time 0.851s down on Russell.
Sergio Perez slotted in fourth 0.899s slower than Russell and the last driver within one second of the benchmark.
Carlos Sainz took sixth, as Charles Leclerc was 11th having struggled with brake problems on the Ferrari.
Alonso best of the rest
A late flyer from Kevin Magnussen followed a good showing in FP1 and earned him a fifth place finish - ahead of both Ferrari, and just three tenths behind the second Red Bull of Perez.
Alonso continued a good start to the weekend for Alpine and was classified in seventh place, ahead of Valtteri Bottas - who won the last Japanese GP - in eighth
Their respective teammates Esteban Ocon and Zhou Guanyu took eighth and ninth - although the Alfa Romeo was nearly 0.6s slower than Ocon's #31 Alpine.
Nicholas Latifi led the Williams duo with 11th as Alex Albon took 12th - although Latifi did suffer an embarrassing moment when he turned in too early for the final chicane and used the wrong bit of track.
He blamed a problem with the car.
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McLaren's early finish
Home driver Yuki Tsunoda was 14th with four-time Suzuka winner Sebastian Vettel the lead Aston Martin in 15th - 3.326s slower than Russell.
In 16th and 17th were the McLaren drivers Lando Norris and Daniel Ricciardo - who ended about 30 minutes early having completed their run plans.
Between them they completed 20 laps, as Russell himself did 21.
Lance Stroll and Pierre Gasly were slowest of all in 18th and 19th - about five seconds off the pace.
Schumacher lost out on running as Magnussen impressed yet again with P5.
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