Lewis Hamilton laid down a marker with the fastest time in first practice for the Italian Grand Prix.
On a set of medium tyres, the world champion punched in a time of 1:20.926 in his Mercedes.
His time was almost half a second quicker than title rival and championship leader Max Verstappen could muster in his Red Bull.
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In a clear indicator that the Mercedes will be quick at Monza, Hamilton’s team-mate Valtteri Bottas posted a time of 1:21.541 - also on medium tyres.
“We are quite pleased,” Mercedes chief Toto Wolff told Sky Sports. “I am actually pretty pleased, but you know how it goes you are all jolly and three hours later you get one on the nose.”
If the pace in Friday’s qualifying is an indicator, Verstappen will struggle to keep tabs on Hamilton. And in what was a poor session for Red Bull, Sergio Perez finished in 10th place - well over a second adrift of Hamilton.
Verstappen leads the drivers' championship by three points from Hamilton.
On the back of the news that he will be heading to Mercedes for the 2022 season, George Russell was down in 17th in his Williams.
Friday is a busy day at the Italian Grand Prix, with qualifying taking place later in the afternoon.
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