The start of the fourth day of testing at Barcelona was a wet one, with the snow from Wednesday still providing a lot of humidity and puddles all over the circuit. With temperatures on the rise though, running was indeed possible, and useful for the F1 teams.
Due to the early conditions, only few drivers went out on track in the first few hours. Stoffel Vandoorne was mostly the only man out on track as McLaren seemed to maximise its track time following time losses on Monday and Tuesday.
Marcus Ericsson joined the party as well, but when he started his 12th lap, he got himself caught in the gravel trap, creating a red flag situation that stopped his running for a good half hour until his team got the car cleaned up again.
Towards 11:00 local time, drivers started switching to intermediate tyres, which was the sign for many teams to also take the opportunity to complete a few more laps. Bottas and Vettel for instance were as such involved in an interesting battle at the top of the timesheet, as each of them improved lap after lap, continuously changing the timesheet until Bottas slashed another 2 seconds off his best to settle that fight on inters.
Times steadily improved throughout the morning, from Vandoorne's first timed lap of 1:59 until 1:25 from Nico Hulkenberg on softs. Only 10 minutes before that, Bottas had been the first to switch to slick tyres, opting for the medium compound himself.
Just like the past two days, this 4th day also features no lunch break, which meant that Hulkenberg went on to improve down to 1:22.507 before returning to the pits at 13:10.
Vandoorne and McLaren returned to the top of the timesheet just 15 minutes later, with 2 subsequent runs on Pirelli's new hypersoft tyres. The Belgian kept on going until around 3, rounding 110 laps before handing the car over to Fernando Alonso.
Similarly, several other teams switched drivers thanks to the improved conditions in order to allow some drivers to recover some of the lost track time from Wednesday. Hamilton took the wheel of the Mercedes AMG F1 W09 while Sauber also switched Ericsson with Leclerc. In the end, it meant that 15 different drivers had driven during the day.
Overall, it was a very productive day for most teams. Mercedes completed 129 laps, Ferrari 120, McLaren 161, Renault 109 and Toro Rosso 147. Kevin Magnussen did 96 laps for Haas, Williams totalled 101 and Sauber 138.
Sergio Perez had his first drive in the new Force India and did 65 laps, but the least active of all was Max Verstappen in the Red Bull RB14 with a mere 35 laps. According to the team, running was limited by a few technical, but easy to fix issues, and was later cut short by Verstappen getting himself caught in the gravel trap.
|1.||Lewis Hamilton||Mercedes AMG||1:19.333||-||69|
|4.||Kevin Magnussen||Haas F1||1:20.317||+0.984||96|
|6.||Carlos Sainz jr||Renault||1:20.940||+1.607||60|
|8.||Sergio Perez||Force India||1:21.973||+2.640||65|
|9.||Max Verstappen||Red Bull Racing||1:22.058||+2.725||35|
|10.||Pierre Gasly||Toro Rosso||1:22.134||+2.801||147|
|12.||Valtteri Bottas||Mercedes AMG||1:22.789||+3.456||60|