Mercedes driver Valtteri Bottas headed Red Bull’s Max Verstappen to set the pace in first practice at the Portuguese Grand Prix.
Bottas was 0.025 seconds ahead of Verstappen and 0.319secs quicker than his Mercedes team-mate Lewis Hamilton.
Seven-time champion Hamilton was fifth fastest, behind Red Bull’s Sergio Perez and Ferrari’s Charles Leclerc.
Hamilton was struggling with his car, trying a number of times to improve but never managing to get a lap together.
Hamilton said early in the session that the Mercedes was “undriveable” because of cold tyres, and seemed to be suffering with an unstable rear later on.
He set the fastest first sector of the lap a number of times, but the time fell away further in the lap.
Verstappen was also struggling, but managed to effectively match Bottas’ time despite suffering heavy vibrations when running on the faster ‘soft’ tyre.
Alpha Tauri’s Pierre Gasly was sixth fastest, ahead of an impressive time from Williams’ George Russell in seventh place, ahead of McLaren’s Lando Norris.
Ferrari’s Carlos Sainz and Alpine’s Esteban Ocon completed the top 10.
It was a session free of major incident, although a high number of drivers had lap times deleted for running wide at Turn Four, and all appeared to be struggling for grip to some extent on the undulating Portimao track on the Algarve.