Lewis Hamilton set the pace for Mercedes as a long red flag period disrupted Practice 1 at the Dutch Grand Prix.
Drivers were hoping to use the opening hour of running to get to grips with the Zandvoort circuit, which returns to the Formula 1 calendar for the first time since 1985 this weekend.
However, a power unit failure for Sebastian Vettel caused the session to be suspended for almost 40 minutes as marshals didn't have the right fire extinguisher for the apparent electrical problem.
This meant his Aston Martin car was 'live' until specialist marshals arrived to carry out the recovery.
Fireman Seb still on shift 🧑🚒#DutchGP 🇳🇱 #F1 pic.twitter.com/TrAvdIYJsN
— Formula 1 (@F1) September 3, 2021
The result was a six-minute dash to set lap times on the soft tyres at the end, initially Ferrari went quickest before Valtteri Bottas and then Hamilton moved to the top of the timesheet.
Home hero Max Verstappen was third after his first flying lap before improving to P2, just under a tenth shy of his championship rival on his second attempt.
Carlos Sainz also went faster as he claimed third, fractionally ahead of teammate Charles Leclerc in fourth as the Italian team made a positive start.
A big issue throughout the session was traffic on the short, narrow Zandvoort track, resulting in a few incidents during the late flurry of action.
Lando Norris, who was quickest before the red flag, had to go off track to avoid colliding with Esteban Ocon in the queue on the approach to the penultimate corner.
Ocon mandando a la hierba a Norris adrede. Sanción it's coming home. pic.twitter.com/ln2T6Gdf3R
— Angel DP (@ANGELDIAZ14) September 3, 2021
The McLaren then went off into the gravel at that same penultimate corner on his flying lap, as he ended up P12.
Elsewhere, Pierre Gasly, Valtteri Bottas and a Haas ended up three-wide through Turn 1 as they battled for track position before ruining each other's laps.
As a result, Bottas ended up fifth ahead of the two Alpines of Fernando Alonso and Ocon.
A clean lap for Antonio Giovinazzi put him eighth, with Lance Stroll and Gasly completing the top 10.
Full results from Practice 1 can be seen below:
