Championship leader Valtteri Bottas edged out Sebastian Vettel to be fastest in Friday's second practice session for Sunday's Chinese Grand Prix.
The Finn set a fastest time of 1 minute, 33.330 seconds in Shanghai in his Mercedes-GP.
Vettel, who had been quickest in first practice, was just 0.027 seconds off the pace in his Ferrari.
Max Verstappen's Red Bull Racing car was third ahead of the second Mercedes of world champion Lewis Hamilton.
There were mechanical issues for Charles Leclerc though. The Ferrari driver, who missed out on a first career win in Bahrain two weeks ago due to engine problems, was sidelined for much of the afternoon as his team checked on cooling issues.
Leclerc was only seventh, 0.8 seconds off the pace of Bottas.
Qualifying takes place at 10am UAE time on Saturday, with the race beginning at 10.10am on Sunday.