Spanish Grand Prix – Lewis Hamilton lead team-mate Valtteri Bottas to give Mercedes a convincing one-two start to their weekend, whilst Vettel and Alonso encountered technical dramas.
The Mercedes pair enjoyed an advantage of almost one second over the Ferrari divers in the opening free practice session.
Hamilton’s medium-compound tyre run saw the Briton register a 1:21.521, a time which was 0.029 of a second faster than Bottas.
In a session which saw the introduction of technical updates for the majority of the field, both drivers were almost one second clear of third-placed Kimi Raikkonen.
Fourth-placed Sebastian Vettel – in the second Ferrari – was forced to sit out of some of the session due to gearbox troubles. However, the four-time champion was able to return to the track before the end of the session.
Similar to much of the season so far, the Red Bull drivers were contesting fifth and sixth place, with Max Verstappen edging out Daniel Ricciardo on this occasion.
The Haas duo of Kevin Magnussen and Romain Grosjean were seventh and eighth respectively, setting times just over two seconds off the pace of the Mercedes cars. Renault’s Nico Hulkenberg and Toro Rosso’s Carlos Sainz completed the top ten.
The Force India’s of Sergio Perez and Esteban Ocon were eleventh and twelfth, ahead of McLaren’s Stoffel Vandoorne.
Vandoorne’s team-mate Fernando Alonso only completed three corners of free practice one after an oil leak resulted in a locked rear axle, sending the McLaren into a spin at turn three and bringing out the red flags.
Felipe Massa was three seconds off the pace in fourteenth in the first Williams, with Daniil Kvyat (Toro Rosso) in fifteenth ahead of the Sauber duo of Marcus Ericsson and Pascal Wehrlein.
Williams’ Lance Stroll ended the session in eighteenth, whilst Renault’s reserve driver Sergey Sirotkin – taking Jolyon Palmer’s place for FP1 – spent much of the 90-minutes in the pits with technical troubles.
To view the full results of the session, click here.