The third-to-last round of the 2018 FIA Formula One World Championship began with practice Friday at Autódromo Hermanos Rodríguez in Mexico City as teams prepared for the Mexican Grand Prix Sunday.

Two 90-minute sessions - FP1 and FP2 - on the 4.304-kilometer (2.674-mile), 17-turn circuit were run under sunny conditions, with Haas F1 Team drivers Romain Grosjean and Kevin Magnussen logging laps 2,200 meters (7,218 feet) above sea level in the region's notoriously thin air.

With far less downforce on the cars compared to similarly fast tracks like Italy's Autodromo Nazionale Monza and Azerbaijan's Baku City Circuit, drivers are forced to compromise between straight-line speed that can reach up to 370 kph (230 mph) and the downforce necessary to push through the track's corners.

Both Grosjean and Magnussen performed the same program in FP1, beginning on the Pirelli P Zero Purple ultrasoft tire before transitioning to the Pink hypersoft. Grosjean's quick time of 1:19.276 came on his 16th lap shod on hypersofts. He ran 26 laps and was the 13th-fastest driver. Magnussen's best time was a 1:19.853 on his 13th lap, also set on hypersofts. He ran 28 laps and posted the 17th-quickest time.

Each ran an installation lap on ultrasofts and stayed with the compound for a nine-lap drive until bolting on hypersofts. It was a scrappy session, as Magnussen encountered traffic during his time on hypersofts but felt they performed better than the ultrasofts despite plenty of graining on both compounds. Grosjean felt an assortment of everything while on hypersofts and came away from the session with the belief the full potential of the tires had yet to be realized.

The struggle for grip on the smooth surface of the Autódromo Hermanos Rodríguez continued in FP2. Grosjean wrapped the session as the 12th-quickest driver with a time of 1:18.733, which was .543 of a second better than his best lap in FP1. His quick time came on the 12th of his 39 laps on a set of hypersoft tires. Magnussen shaved .183 of a second off his FP1 time with a lap of 1:19.670, but fell to 20th on the speed chart. His fast lap came on his 14th tour, also while utilizing the hypersoft tire. He completed 35 laps.

Grosjean began FP2 on Red supersoft tires and then switched to hypersofts. Magnussen mimicked his FP1 program by starting on ultrasofts before bolting on hypersofts. Both drivers ran nine laps on their respective compounds before moving to hypersofts.

Between the two sessions, Haas F1 Team ran a total of 128 laps - 65 by Grosjean and 63 by Magnussen.

Romain Grosjean: "Not an easy day to find the balance of the car and getting the tires to work. The hypersofts weren't having a good time. We were suffering, as well, with the cooling and the altitude. There's a lot to work on with the car. It wasn't the performance we were expecting. I think the order is a bit surprising - the Renaults are very competitive, as was the Toro Rosso of (Brendon) Hartley, and Ferrari were a bit behind. There's a lot of work to be done tonight. Hopefully, it'll be a better day tomorrow. The exciting part is it looks like we'll have more than one stop in the race."

Kevin Magnussen: "It wasn't a good day. We didn't learn too much. The tires were just not working at all. We'll see what we can do on the tire side to get them into the window tomorrow. They weren't working on low fuel or on high fuel. We're looking for answers. We'll have to think hard and come up with some ideas for tomorrow. I didn't get my first lap in. I had to try again, but the tires had already died by then. It's not as bad as it looks. It's just frustrating when you want to go racing and you're sliding around like crazy and the car isn't behaving as you expected. We'll see what we can do for tomorrow."

Guenther Steiner: "Not our best FP1 and FP2 sessions of the season. We were struggling with getting the tires to work, to get them into their working range. There needs to be a lot of thinking happening tonight. Hopefully, we come out better tomorrow. I'm sure our guys will come up with some solutions. At the moment, the chance of rain is high. Maybe we'll do all this work for nothing. Not a fantastic day, though."

Check out our Friday gallery from Mexico City, here.