Barcelona, Spain: Valtteri Bottas completed a perfect double for Mercedes on Friday when he headed team-mate Lewis Hamilton in the second free practice for this weekend’s Spanish Grand Prix.
The world championship leading Finn, who is one point ahead of the defending five-time champion after the pair's record four successive season-opening one-twos, was half a tenth quicker than the Briton and had been fastest in the morning session.
Charles Leclerc was third ahead of his Ferrari team-mate Sebastian Vettel, the two failing to break the Mercedes domination despite the introduction of an updates package.
Max Verstappen was fifth for Red Bull ahead of Romain Grosjean of Haas, Pierre Gasly in the second Red Bull and Dane Kevin Magnussen in the second Haas.
Spain's Carlos Sainz was ninth for McLaren and Daniil Kvyat 10th for Toro Rosso.
The session was run in warm, dry conditions and was largely incident-free as the teams returned to Europe for the first time this year.