Max Verstappen top in Malaysian Grand Prix first practice
Red Bull's Max Verstappen and Daniel Ricciardo were one-two in a wet first practice at the Malaysian Grand Prix.
The Dutchman was 0.757 seconds clear of his team-mate as McLaren's Fernando Alonso took third.
Ferrari's Kimi Raikkonen and Sebastian Vettel were next, ahead of championship leader Lewis Hamilton's Mercedes.
The start of the session was delayed by half an hour because of heavy rain before conditions cleared enough for cars to run.
There were some impressive performances among the rookies who had their first experience of an F1 race weekend in difficult conditions.
Frenchman Pierre Gasly was ninth fastest for Toro Rosso, where he is replacing the dropped Daniil Kvyat for at least this race and the next one in Japan.
And at Sauber, Monaco's Charles Leclerc, the Formula 2 championship leader, was 16th, 0.3secs ahead of regular driver Pascal Wehrlein.
The list of fastest times was not necessarily representative of pace because of the different times of the session drivers set them.
Raikkonen and Vettel, for example, popped up into their final positions with their very last laps, whereas Hamilton's time was set some minutes earlier.
The Briton is 28 points ahead of Vettel heading into the race weekend, with six races to go and 150 points remaining.
Despite the wet conditions, there were no major incidents.
Both Ferrari drivers had minor off-track moments without damaging their cars, while Renault reserve driver Sergey Sirotkin had a half-spin at Turn Two before ending up 10th fastest, just ahead of his team-mate Jolyon Palmer.