Valtteri Bottas headed a Mercedes 1-2 in opening practice for Formula 1’s Emilia Romagna Grand Prix in an FP1 session that was disrupted by a collision between Sergio Perez and Esteban Ocon.

Bottas shot to the top of the timesheets with a 1m16.564s after a red flag stoppage during a frantic 60 minute practice session as F1 returned to action at Imola following a three-week break.

The Finn outpaced Mercedes teammate Lewis Hamilton by just 0.041s, with Red Bull’s Max Verstappen third-fastest and only 0.058s adrift.

F1 2021- Imola GP Race Preview

FP1 was halted with around 25 minutes left on the clock after what appeared to be front right to rear left contact between Perez and Ocon at the Variante Villeneuve.

The incident was missed by the cameras amid technical issues that hampered F1’s world broadcast feed throughout practice, but Perez’s left-rear was completely destroyed, while Ocon pulled over further down the road with his front-right out-of-kilter. Both drivers have been summoned to the stewards following FP1 over their unseen incident.

Behind the top three came Ferrari’s Charles Leclerc and AlphaTauri driver Pierre Gasly, who along with sixth-placed Carlos Sainz had a spell at the top of the FP1 order before the pair ended the session with the exact same time on a 1m16.888s.

Returning two-time world champion Fernando Alonso was seventh for Alpine, while Lance Stroll, Nicholas Latifi and Daniel Ricciardo completed the top-10 for Aston Martin, Williams and McLaren respectively.

A number of drivers suffered spins and off-track throughout the session, which came to a close with Haas rookie Nikita Mazepin spinning into the wall at the final corner after getting onto the gravel.