Mercedes driver Lewis Hamilton topped the second Formula 1 free practice session for the Spanish Grand Prix
Hamilton posted a best time of 1m18.259s early in the 90-minute session using soft-compound Pirellis.
He looked set to improve on his qualifying simulation flying lap after switching to supersofts, but was too aggressive on the throttle in the Turn 7 left-hander and took a bite of the gravel.
Hamilton did not have another serious attempt on that set of tyres before returning to the pits, but with many drivers struggling to make a significant improvement after switching to supersofts his earlier time was good enough for top spot.
Daniel Ricciardo was second fastest for Red Bull, 0.133s slower than Hamilton, also posting his time using soft Pirellis on his first run.
Ricciardo posted his time on his 10th lap on the softs, then lapped three tenths slower on his quickest attempt using the supersofts.
Red Bull teammate Max Verstappen did manage to improve on his qualifying simulation lap, posting a 1m18.533s to slot into third behind his team-mate.
Verstappen later had a spin at Turn 2 while lapping on softs in the closing minutes of the session.
Behind him, Sebastian Vettel also improved on supersofts, lapping half-a-tenth slower than Verstappen, with Valtteri Bottas behind the pair in fifth having used mediums early on then set his best time on supersofts.
Kimi Raikkonen was the slowest of the drivers from the top three teams, surviving a run through the gravel at Turn 4 before bringing his car into the pits with just under 40 minutes remaining with an unidentified problem.
He also did not improve on supersofts, with his best of 1m18.829s set on softs early in the session.
Romain Grosjean recovered from a disastrous start to the afternoon's running to emerge as best of the rest after posting a 1m19.579s using supersofts just after the one-hour mark.
The Haas driver spun into the gravel at Turn 7 on his fourth lap of the session, but after being recovered to the pits returned to the track to post his time.
That relegated Kevin Magnussen to the second fastest Haas driver in eighth place.
Magnussen had been best of the rest early in the session before improving his best time by 0.235s on supersofts.
That put him ahead of Stoffel Vandoorne, driving the updated McLaren, the Belgian having a slow start to the session thanks to a floor change before he secured ninth place with his pace on supersofts at close to the one-hour mark.
Sergio Perez completed the top 10 for Force India, less than a tenth of a second faster than teammate Esteban Ocon.
Perez's session came to a premature end as he stopped on track with 13 minutes remaining with a loose front-left wheel after a pitstop.
Although he was briefly able to restart and continue to roll around in an attempt to get back to the pits after being urged to attempt to do so by the team, he decided he had to stop for good for fear the wheel was going to come off completely.
Fernando Alonso was 12th fastest for McLaren ahead of the lead Renault of Nico Hulkenberg and the Toro Rosso of Pierre Gasly – the latter also having a floor change during the session.
Sauber pairing Marcus Ericsson and Charles Leclerc were 15th and 16th, ahead of the second Renault of Carlos Sainz.
Sainz complained of problems with both aerodynamic and mechanical balance in the Renault, which features a modified front wing and rear suspension.
Brendon Hartley was 18th ahead of the two Williams drivers, with Sergey Sirotkin ahead of Lance Stroll despite describing the car's handling as "weird" over the radio.
|2||Daniel Ricciardo||Red Bull||TAG||41||1'18.392||0.133|
|3||Max Verstappen||Red Bull||TAG||39||1'18.533||0.274|
|10||Sergio Perez||Force India||Mercedes||28||1'19.962||1.703|
|11||Esteban Ocon||Force India||Mercedes||38||1'20.024||1.765|
|14||Pierre Gasly||Toro Rosso||Honda||32||1'20.373||2.114|
|17||Carlos Sainz Jr.||Renault||Renault||31||1'20.672||2.413|
|18||Brendon Hartley||Toro Rosso||Honda||34||1'21.265||3.006|