Valtteri Bottas has finished 1.4s ahead of Charles Leclerc at the top of the order on the first day of the post-race Formula 1 test at Barcelona.
Bottas was fastest in the morning on C3 tyres, the softest compound for the grand prix weekend, before setting a 1:15.511s on C5 tyres (softest in the range) in the afternoon.
That time was just over a tenth slower than that which the Mercedes driver clocked to take pole position three days earlier.
“We completed a lot of laps and learned a lot,” said Bottas, whose haul of 131 laps was two shy of the highest number completed by a driver during the day.
“Our programme focused on the tyres and setup. We collected lots of data over the race weekend in similar conditions to what we had today in terms of temperature and wind, so it was nice to do some setup comparisons.
“There were some new mechanical test items on the car too which were interesting to try out.”
Leclerc only had C2 tyres on his Ferrari when he set the 1:16.933s which would put him second quickest, while Scuderia Toro Rosso’s Daniil Kvyat was third with a 1:17.679s on C4 tyres.
Renault’s Nico Hulkenberg was fourth on C3 tyres, less than a tenth quicker than Pierre Gasly on the same compound.
Gasly did, however, miss the final hour and then some, having pulled up with a transmission problem in the Red Bull.
Carlos Sainz (McLaren) was sixth, from Pietro Fittipaldi (Haas), Racing Point simulator driver Nick Yelloly, Sebastian Vettel (Ferrari), and Lando Norris (McLaren).
Both Vettel and Sergio Perez, who ended up 11th in his Racing Point car, were testing for Pirelli, while Sainz and Norris shared duties for McLaren.
Callum Ilott completed only 41 laps after crashing the Alfa Romeo at Turn 3, midway through the afternoon session.
He was uninjured despite the sizeable impact and still ended up faster than the Williams of Nicholas Latifi.
Testing continues at the Circuit de Barcelona-Catalunya on Wednesday (local time).
Results: Formula 1 In-Season Test, Barcelona, Day 1
|3||Daniil Kvyat||Toro Rosso||1:17.679||C4||121|
|5||Pierre Gasly||Red Bull||1:18.140||C3||118|
|8||Nick Yelloly||Racing Point||1:18.361||C5||111|
|9||Sebastian Vettel||Ferrari||1:18.485||Pirelli test||133|
|11||Sergio Perez||Racing Point||1:19.719||Pirelli test||118|
|12||Callum Ilott||Alfa Romeo||1:19.819||C2||41|