Mercedes driver Nico Rosberg set the fastest time in Friday's opening practice session at the Japanese Grand Prix, edging out teammate and Formula One championship leader Lewis Hamilton.
Rosberg, who lost his championship lead to Hamilton last time out in Singapore, clocked a lap of 1 minute, 35.461 seconds at the Suzuka circuit, 0.151 seconds ahead of Hamilton.
Hamilton leads Rosberg by three points heading into Sunday's race.
Max Verstappen, who turned 17 on Tuesday, became the youngest driver to take part in a Formula One Grand Prix weekend, finishing twelfth fastest and only four tenths of a second off the pace of teammate Daniil Kvyat.
Fernando Alonso, who is holding talks over his future with Ferrari, was third fastest followed by Williams' Valtteri Bottas.