Charles Leclerc set the early pace as morning rain led to an incident-packed first practice at the Italian Grand Prix.
On a drying track, lap times tumbled around eight seconds from the start to the end with the Monegasque posting a 1m27.905s during a brief flurry of late laps on the slick tyre.
The session began with drivers on the full wets before quickly switching to the intermediates. Getting the tyre upto temperature was proving a big challenge, however, and resulted in many slides and near-spins throughout.
Kimi Raikkonen would be the first to hit the barrier though, as the rear snapped applying the throttle through Parabolica causing the first of two quick-fire red flags.
The second would come after Sergio Perez lost control on the final apex of Ascari, spinning into the barrier on the inside.
After that, drivers were able to complete some solid running but for a brief stoppage after Gasly got beached on the kerb at the first chicane.
As conditions improved, Mercedes moved to the front on intermediates with Valtteri Bottas ahead of Lewis Hamilton.
In the final minutes though, Ferrari triggered a few laps of slick tyre running as the main straight dried enough to make them useable.
Despite some initial caution, Leclerc would jump to the top with his final lap on the mediums, beating the two McLaren’s who impressed on the still damp track in places.
Lewis Hamilton spent his dry tyre run in the slipstream of Sebastian Vettel and would move upto fourth with his last lap in the Mercedes.
Alex Albon also appeared comfortable in fifth for Red Bull, a second clear of Max Verstappen in seventh who came out very late on the slicks.
In between sat Daniil Kvyat as the combination of Monza’s straights and wet conditions suited his Toro Rosso.
Sebastian Vettel struggled to get upto speed on the medium tyre finishing 2.6s slower than Leclerc in eighth with Bottas ninth having spun at the first chicane on his final lap.
Despite his earlier moment, Gasly would round out the top 10 in the second Toro Rosso.
While perhaps not very informative in terms of an early pecking order, the session at least offered an insight into the challenges that await should it rain on Sunday.
Teams though will be hoping for a fully dry track to complete some serious setup work on their low downforce packages, including both qualifying and race simulations in the afternoon.
Full results from Practice 1 can be seen below:
