Fernando Alonso emerged fastest in the first practice session for the Formula 1 Japanese Grand Prix in a wet session.
Heavy rain battered Suzuka as F1 returned for the first time since 2019, with nobody taking to the track when the session went green.
Fortunately conditions improved slightly to allow some intermediate running for about half an hour where all of the lap times were set.
Alonso's 1m:42.268s effort was good enough to secure P1 - the first time he has done so since FP3 at the Canadian Grand Prix in June.
Ferrari duo Carlos Sainz and Charles Leclerc slotted in behind, with Alonso's Alpine teammate Esteban Ocon and Kevin Magnussen of Haas rounding out the top five.
Max Verstappen was sixth for Red Bull, with Lewis Hamilton 13th for Mercedes.
Slow start to FP1 at Suzuka
The Haas of Magnussen and home driver Yuki Tsunoda in the AlphaTauri were the first drivers out to explore Suzuka on the Wet Pirelli tyres, with Mick Schumacher's 1m:52.537s attempt the first timed lap of the 60-minute session.
Leclerc called for a switch to Intermediates, with a flurry of fast laptimes being traded by the Ferrari duo still on the full wets.
The Monegasque got down to a 1m:48.1s in this segment of the session, but was 0.346s down on teammate Sainz's 1m:47.758s.
Verstappen emerged 30 minutes into the session to post a 1m:44.059s time on the Inters - some 3.699s clear of Sainz in P2.
A second round of trading laptimes followed between Verstappen, Ocon and Sainz - who went fastest on a 1m:42.563s - 0.071s up on the #16 Ferrari.
That was until Alonso popped in the 1m42.268s - 0.315s in the black - to go P1 just as the heavy rain began to fall once again at Suzuka.
Leclerc found conditions difficult and skated off the race and into the gravel at the Degner Corners.
This all but ended the competitive running of the session with about 15 minutes to go, although a cars did return to the track towards the end to complete some laps ahead of practice starts on the grid.
In the dying embers of the session, Mick Schumacher hit the barriers hard on the exit of Dunlop, destroying the front end of his Haas and preventing him from taking to the track in FP2.
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Trouble for Russell in Mercedes
Schumacher, Lando Norris, defending race winner Bottas and Sergio Perez rounded out the top 10 for the session.
Zhou Guanyu was the first driver outside the top 10, ahead of Daniel Ricciardo and Lance Stroll in the McLaren and Aston Martin - about 2.3s off the pace.
Lewis Hamilton placed 13th in the Mercedes, having not taken to the track during the Wet tyre stage, an outlap aside.
The final places were shared between the Williams, AlphaTauri, and Mercedes drivers with Vettel 20th.
Alex Albon was 15th ahead of Pierre Gasly and Nicholas Latifi who skated off the track at the hairpin on the full wet tyres.
George Russell was forced to change his engine ahead of practice to the one Mercedes were planning in using for Saturday and Sunday, and only made four timed laps, ahead of Tsunoda and Vettel, who is in his final Japanese Grand Prix weekend.
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