Nico Rosberg set the initial pace for the Italian Grand Prix weekend by topping the opening practice session ahead of his team mate Lewis Hamilton, as Mercedes again had a comfortable advantage over its rivals.
Rosberg's best time of 1m 22.959 was two tenths of a second better than Hamilton's mark, as well as beat last year's pole time by around four tenths.
The two Mercedes pilots swapped places at the top several times early in the session, first with both on the soft Pirelli prototype test compound and then later with the supersoft tyres on. About half an hour into the session indeed Hamilton pipped Rosberg's supsersoft time by a scant 0.008 seconds.
Later though both Mercedes switched to the soft tyre and went even quicker. Rosberg set a 1m 22.959 and Hamilton shortly afterwards could not match it, setting a 1m 23.162.
The Ferraris featuring an upgraded Ferrari unit, were best of the rest. A late run put Kimi Raikkonen third although his 1m 24.047 on the soft tyre was some 1.088 seconds shy of the Mercedes pace. Sebastian Vettel was next up in P4, although his 1m 24.308 – a quarter of a second off Raikkonen's best – while also on the soft tyre was set much earlier in the session.
Sergio Perez impressed in the Force India by setting fifth best time, 1.691 off Rosberg's pace, also on the soft. Force India reserve driver Alfonso Celis – taking part in this session instead of Nico Hulkenberg – set 12th best time, around seven tenths off Perez.
Valtteri Bottas – like Perez with a Mercedes engine – also set competitive times and finished up in P7, 1.826 seconds off the top.
Romain Grosjean in Haas – like the works team also using the upgraded Ferrari power unit – set a fine late time on the supersoft to finish up in P6, 1.804 seconds off the pace, while his team mate Esteban Gutierrez was three tenths off him in P9.
Red Bull had a quiet session, with Max Verstappen eighth in the final order and Daniel Ricciardo two places back, and both more than two seconds off the pace. Verstappen mentioned not getting enough brake temperature on his best run as well as having traffic.
