Valtteri Bottas topped the times for Mercedes ahead of McLaren’s Carlos Sainz after championship leader Lewis Hamilton was forced to swerve off track and avoid a collision in Saturday’s stoppage-hit final free practice for Sunday’s Italian Grand Prix.
The Finn, determined to claim a front row start and boost his title challenge, clocked a best lap in one minute and 20.089 before a late interruption, when the action was paused by red flags after Daniel Ricciardo parked his spluttering Renault with suspected electrical problems.
Bottas’s best lap left him two-tenths clear of Sainz, who squeezed in a dazzling lap with seconds remaining after the late re-start, with Lando Norris third in the second McLaren, three-tenths adrift.
Ricciardo was fourth ahead of Hamilton, in the second Mercedes, the six-time champion having been forced to take dramatic avoiding action at around 300 kph when he approached two slow cars running side by side at the approach to the Parabolica.
It appeared that one of the Haas cars had moved into the centre of the track ahead of Hamilton, forcing him to flick his car to the right and run partly across the grass as his flying lap was ruined in the most dangerous way.
Behind Hamilton, Max Verstappen was sixth ahead of his Red Bull team-mate Alex Albon, Esteban Ocon in the second Renault, Lance Stroll and his Racing Points team-mate Sergio Perez.
The Ferraris of Charles Leclerc, who won from pole position last year, and his departing team-mate four-time champion Sebastian Vettel, were 11th and 15th.
On another near-perfect late summer’s day in northern Italy, the air temperature was 27 degrees and the track 39 when the two Alfa Romeos began the action, followed by the Haas cars and Norris in his McLaren.
Norris’s team-mate Sainz then emerged and finally clock a flying lap time in 1:21.875 after 19 minutes.
Almost immediately, the rest of the teams joined the fray and, after half an hour, Hamilton set a best lap in 1:20.658, half a second slower than his fastest in Friday’s second practice.
The champion was soon usurped by Bottas, chasing his first front row start at Monza, and then Verstappen.
With 15 minutes remaining, the two Mercedes re-emerged.
Bottas responded with a lap in 1:20.089 to move three-tenths clear of Verstappen, his right wheels on the white line at the Parabolica, but not beyond it. The lap did not attract the stewards’ attention and stood.
Hamilton improved to within 0.35 of his team-mate on worn softs, a lap that suggested it would be an intra-team duel for pole later in qualifying until, in a final flurry with seven minutes remaining, Norris and Ricciardo improved to take second and third.
For the luckless Australian, it was his last run of the session as he pulled up and parked on approach to the first Lesmo. “I have an issue,” he radioed in to Renault as red flags stopped the session to allow for the car’s recovery.
As soon as that was done, with three minutes remaining, the field left a crowded pit lane, all on softs, for a last flying and spectacular run.