Rosberg ahead in first practice at Monza

F1 Grand Prix, GP Italy, Autodromo Nazionale di Monza

Nico Rosberg was the fastest man at Monza during the first practice session, topping his Mercedes team mate by 2 tenths. Ferrari, running upgraded engines this weekend, were more than a full second off the pace, but still the closest challengers.

The Ferrari duo ran notably less laps than their Mercedes rivals, sitting in the pits for longer periods as the team was checking the functionality of the upgraded power unit. Both drivers were also explicitly told at the beginning of the session that they would have limited mileage.

Behind Ferrari was Sergio Perez as 5th fastest, confirming Force India's pace as seen at Spa-Francorchamps as well. Romain Grosjean was 6th fastest in the Haas, also with Ferrari's upgraded power unit, ahead of Bottas. Verstappen, Gutierrez and Ricciardo completed the top 10.

Early on in the session, more drivers tested the Halo device, including Perez, Ricciardo and Button. The latter was also timed by FIA technical delegate Jo Bauer as he tried to get out of the car to test the safety implications of the device.

Teams were also given the same Pirelli prototype tyres as in Spa, featuring the soft rubber compound with a stiffer structure on the rears.

Problems arose for some towards the end of the session, with Wehrlein suffering a DRS failure and as a result ending 1s down on his teammate Ocon. Fernando Alonso had a gearbox problem at the end, with the Spaniard lapping the circuit unable to shift gears.