Mercedes driver Lewis Hamilton posted the fastest lap time during Friday's opening free practice session for the Italian Grand Prix, ending up almost half a second clear of Red Bull rival Max Verstappen.
It was a busy hour of running at Monza, as F1 trials the new 'Sprint' format for only the second time, with drivers and teams in a hurry to gather as much information as possible before qualifying later in the day.
Around 40 minutes of the session was dedicated to longer runs on a mixture of the Hard (C2) and Medium (C3) compound tyres. In the closing stages, a selection of teams, including Red Bull, made the switch to the Soft (C4), but Mercedes opted against using the red-marked rubber.
Hamilton's benchmark time of 1:20.926 on Mediums put him 0.452s ahead of the Soft-shod Verstappen, which is in line with expectations that Mercedes will hold the advantage over Honda-powered Red Bull this weekend.
Hamilton did, nonetheless, benefit from a small slipstream behind AlphaTauri's Yuki Tsunoda on his way to the top of the times.
Lando Norris had looked set to split Hamilton and Verstappen with a late effort in his Mercedes-powered McLaren, but the lap time was deleted for exceeding track limits, dropping him out of the top 10 positions.
Departing Mercedes driver Valtteri Bottas (also on Mediums) was a further half a tenth adrift in third.
Result Free practice 1 - Italian
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Aston Martin, another Mercedes-powered team, enjoyed a strong first session as Lance Stroll and Sebastian Vettel placed fourth and sixth respectively, sandwiching the AlphaTauri of last year's surprise race winner, Pierre Gasly.
Carlos Sainz was the fastest of the Ferrari drivers in seventh, albeit almost a second off the pace after a scruffy Soft-tyre run amid heavy traffic, with teammate Charles Leclerc having a similar experience back in 11th – also losing a competitive time for exceeding track limits.
Alpine's Fernando Alonso, McLaren's Daniel Ricciardo (another who lost an improved time) and Red Bull's Sergio Perez rounded out the top 10 places.
All cars will now be put into parc ferme conditions, ahead of Friday evening's qualifying session, meaning the teams can make no further changes.
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