The fifth round of the 2017 FIA Formula One World Championship began with practice Friday at the Circuit de Barcelona - Catalunya as teams prepared for the Spanish Grand Prix Sunday.

Two 90-minute sessions - FP1 and FP2 - on the 4.655-kilometer (2.892-mile), 16-turn track were run under glorious sunshine and warm temperatures, a vast departure from when teams were in Barcelona two months ago for winter testing.

Haas F1 Team drivers Romain Grosjean and Kevin Magnussen enjoyed their best FP1 session of the season, with Magnussen securing the seventh-fastest time and Grosjean just behind him with the eighth-quickest time.

Magnussen's fast lap of 1:23.670 came on his 14th tour of the circuit with his Haas VF-17 shod on Pirelli P Zero White medium tires. And with Grosjean on the same program as his teammate, he also secured his best time - a 1:23.758 - on his 14th lap utilizing the medium compound.

The two drivers started FP1 on the hardest and most durable tire in Pirelli's range - the P Zero Orange hard. Both Magnussen and Grosjean completed 11 laps on the hard tire before switching to the medium. Magnussen put down 11 more laps with the medium tire and Grosjean turned 12 laps to bring their FP1 lap totals to 22 and 23, respectively.

Leading the way in FP1 was Mercedes driver Lewis Hamilton, whose fast lap of 1:21.521 was .029 of a second better than the next quickest time of Valtteri Bottas, his teammate.

As temperatures warmed before and during FP2, the handling of Haas F1 Team's cars changed. Magnussen immediately described his car as very hard to drive with no rear grip. And after a lockup on his first lap, Grosjean said his car handled differently, with a long brake pedal exacerbating the feeling. Progress was made as the session evolved, as both drivers improved on their FP1 times, but other teams made progress too. In the end, Grosjean was 11th quick with a 1:22.371, which was 1.387 seconds better than his best FP1 time. Magnussen shaved .663 of a second off his FP1 time with a best lap of 1:23.007.

Both drivers ran the same tire compounds in FP2, switching between the White medium and Yellow soft. With the soft being the grippiest tire in Pirelli's lineup, it was no surprise that it helped secure each driver's fastest lap. Grosjean's quick time came on his 12th tour and Magnussen's fast time came on his 10th lap. Grosjean ended FP2 with 36 laps while Magnussen recorded 32 laps.

The Mercedes duo of Hamilton and Bottas topped FP2, with Hamilton's time of 1:20.802 bettering Bottas' mark by .090 of a second.

Romain Grosjean: "It's not been an easy day. We've been dealing with a lot of things. I think the tires are struggling a bit here to work, or at least we're struggling to get the tires to work. I don't think we're the only ones - a lot of cars have been running wide. So that's going to be key, getting those correct. If we can do that, we can gain a lot of lap time. We just focused on more work this afternoon, seeing what other tools could be available so we can put everything together for tomorrow."

Kevin Magnussen: "We had a good morning and got some good data on the car. There wasn't really much useful learning in FP2. The track was very different and the car wasn't behaving as expected. We'll look into that and hopefully improve it for Saturday. It's not quite clear yet why we were happy this morning and not in the afternoon. It was a lot windier this afternoon, but then that was the same for everyone. We looked less competitive and we need to try and understand that. Hopefully, we can get back to where we know we should be."

Guenther Steiner: "It was a good first session this morning. We got a lot of data, which we still need to go through. It was a more difficult one in the afternoon with the higher temperatures. On the long runs we had challenges. We need to analyze what is next. There's a lot of work to do this afternoon. Again, we need to go through the data and understand why. We also need to get more data on the new floor. Romain running the new floor tomorrow morning will hopefully help us, and then after that we can make a decision about which one to use going forward."

Check out our Friday gallery from Barcelona, here.