Bottas and Hamilton top FP1 on ultrasofts

Mercedes drivers Valtteri Bottas and Lewis Hamilton were fastest in the first free practice session for the Mexican Grand Prix. Both set their fastest laps on ultrasofts, while both Red Bull and Ferrari opted to stay on supersofts.

The session was briefly red-flagged after an accident involving Force India development driver Alfonso Celis.

Mexican Grand Prix - Free practice 1 results

Despite being bathed in sunshine, the high-altitude Autódromo Hermanos Rodríguez felt on the distinctly chilly side as cars exited pit lane on Friday morning in Mexico City.

The two McLarens were at the head of the line when the track went green, Stoffel Vandoorne sporting the halo cockpit protection device. However, the Belgian driver was immediately sidelined with a power unit issue that forced him out the rest of the session without setting a time.

Replacing Romain Grosjean in the Haas for FP1, Antonio Giovinazzi was the first driver to set a timed lap. He quickly whittled his initial time down to 1:23.841s on the soft tyres.

Inevitably, Giovinazzi was swiftly ousted from the top of the timesheets once the Mercedes drivers got to work. Valtteri Bottas was over two seconds faster with his first effort on supersofts, but Lewis Hamilton initially went off onto the grass at turn 3.

Unflustered, Hamilton bounced back minutes later. He set a new benchmark of 1:19.815s, already a second faster than his own top time in last year's FP1. He and Sebastian Vettel then traded the top spot back and forth, before Vettel became the first driver under 1:19s as the 40-minute mark approached.

With their first set of tyre duly returned to Pirelli, Mercedes moved on to ultrasoft compounds. Bottas duly wiped a full second off Vettel's time with 1:17.824s, 0.466s faster than Hamilton and almost nine tenths faster than last year's pole. Mercedes went on to complete more laps than any other team. However, the Ferrari and Red Bull drivers stayed on supersofts for the duration.

A water leak for Kevin Magnussen after five laps meant that the Haas was stuck in the garage for a significant proportion of the session. Max Verstappen had a likewise curtailed session after Red Bull committed to a major set-up change on the RB13. Nico Hulkenberg also had limited running after a "little leak" was found on his Renault.

An engine stoppage for Brendon Hartley at turn 4 triggered a Virtual Safety Car after 35 minutes. While the Toro Rosso eventually got going, the engineers spent the rest of the session investigating the problem.

Kimi Raikkonen had just undergone a harmless slow spin at turn 5 when the session was red-flagged just before the one-hour mark. Force India's development driver Alfonso Celis had lost the back of the car at the final corner and gone rear-first into the barriers, incurring heavy damage in the process. The session resumed after a 10 minute hiatus for track clean-up.

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