MONTMELO, SPAIN - MARCH 02: Romain Grosjean of France driving the (8) Haas F1 Team Haas-Ferrari VF-17 Ferrari locks a wheel under braking on track during day four of Formula One winter testing at Circuit de Catalunya on March 2, 2017 in Montmelo, Spain. (Photo by Dan Istitene/Getty Images)

The first official preseason Formula One test came to a close on Thursday with a simulated wet Barcelona Circuit. The track was artificially dampened so that teams could test the new 2017 wet weather Pirelli rubber so that the teams could better gauge how this year’s new, wider tyre would perform.

A fully soaked track greeted Haas driver Romain Grosjean who was using the Pirelli Cinturato Blue full wet to record nine laps. As the sun rose and the track began to dry, teams transitioned to the Cinturato Green intermediate tyre which Grosjean used for a further 26 laps until the track was dry enough for slicks.

With a relatively dry track, the Frenchman set out for an eight-lap run on a used set of Pirelli P Zero White medium tires. With less than 10 minutes remaining before the mandatory lunch break, the team bolted four new Red supersoft tires onto the Haas VF-17. Grosjean hit the track for five laps, securing his best time of the morning session on his 49th and final lap – a 1:22.739 that put him second overall, .434 of a second behind Scuderia Ferrari’s Kimi Räikkönen.

Water trucks doused the track again during the lunch break, forcing teams back onto the full wet tire to start the afternoon session.

Grosjean knocked out 69 laps in the day’s second half, smashing the 56 total laps he earned on Wednesday and just as he had in the morning session, Grosjean ran through Pirelli’s tire lineup as track conditions evolved.

Nine laps were run on the full wet tire with 19 laps on the intermediate. By 4:20 p.m. local time, the track was ready for a return to slicks and the team put four new White mediums on the Haas VF-17. During the swap from intermediates to slicks, Haas F1 Team crew members practiced numerous pit stops, for the car isn’t the only component that needs to be ready for the season-opening Australian Grand Prix March 26 in Melbourne.

Riding on slicks for the day’s final 100 minutes, Grosjean tried out different setup configurations. His best time of the afternoon turned out to be his best time of the day – a 1:22.309 on his 111th lap with a set of Red supersofts that nicked his best time from the morning session by .430 of a second. The lap put Grosjean fourth among the 10 drivers who participated in the day’s test.

Grosjean led the day in laps, tallying 118 tours around the circuit, 25 more than second-best Räikkönen. It marked the second time Haas F1 Team ran the most laps this week in testing, as teammate Kevin Magnussen also ran 118 laps on Tuesday, 10 more than Räikkönen, who ran the second-most laps that day as well.

“It’s been a productive day for us,” Romain said. “We managed to get some wet running, inter running, pit stop practice, dry running and trying a few setup changes that we had thought about overnight. The car is getting better and better. The team is doing a great job. Our pit stops looked pretty good. We’re trying to understand as much as we can. Of course, this is winter testing and it’s never going to get close to the conditions we have over a race weekend but, generally, I think we’ve made some good progress today. Hopefully, we can analyze all of that over the weekend and come back stronger next week.”

After four days of testing at Barcelona, Haas F1 Team racked up 343 laps for a total of 1,596.665 kilometers (992.122 miles). Magnussen secured 169 of those laps (786.695 kilometers/488.83 miles) on Monday and Tuesday, and Grosjean accounted for 174 laps (809.97 kilometers/503.292 miles) on Wednesday and Thursday.