Toro Rosso rookie Carlos Sainz has begun the Japanese Grand Prix weekend by topping the standings in a very wet first practice session.
The 21-year-old finished above Red Bull's Daniil Kyvat with a lap of 1:49.434 - just over half a second faster than his nearest rival.
Mercedes driver Nico Rosberg finished the session in third place, a tenth of a second slower than Kvyat, while his teammate and championship title rival Lewis Hamilton was a further six tenths of a second behind the German in fifth.
Singapore Grand Prix winner Sebastien Vettel separated the two Mercedes drivers in fourth place, with a lap of 1:50.519.
The session was disrupted by very heavy rain, and only 12 drivers were able to post a time.
Full standings:
1. Carlos Sainz (Toro Rosso)
2. Daniil Kyvat (Red Bull)
3. Nico Rosberg (Mercedes)
4. Sebastien Vettel (Ferrari)
5. Lewis Hamilton (Mercedes)
6. Max Verstappen (Toro Rosso)
7. Kimi Raikkonen (Ferrari)
8. Felipe Massa (Williams)
9. Marcus Ericsson (Sauber)
10. Valtteri Bottas (Williams)
11. Felipe Nasr (Sauber)
12. Jenson Button (McLaren)