2015 Russian GP: Hulkenberg fastest in first practice

Sochi, Russia - A diesel spillage by a circuit-cleaning vehicle delayed Friday's opening free practice session for this weekend's 2015 Russian Grand Prix (October 10-11) and reduced it from 90 minutes to one hour.

The worst of the spillage was at Turn Eight on the Sochi Autodrom Olympic Park track created in the coastal cluster facilities built for the 2014 Winter Olympic Games.

Slippery surface

After emergency washing of the track, the session began late, four-time world champion Sebastian Vettel of Ferrari commenting "what a mess" as he drove through the drying patch for the first time.

Read:F1 statistics: 2015 Russian GP

We're so excited, and we just can't hide it #RussianGP #redseason pic.twitter.com/EZvj4Ij5Pb

— Scuderia Ferrari (@ScuderiaFerrari) October 9, 2015

The track conditions were declared officially as "wet" and this meant drivers ran on intermediate and full-wet tyres to cope with the slippery surface left by the diesel and its aftermath.

Nico Hulkenberg topped the times for Force India in Friday's delayed and curtailed opening free practice session.

The German, who won the 2015 Le Mans 24 Hours, timed his best lap perfectly at the end of a session cut to only an hour's action by a diesel spillage from a circuit cleaning vehicle.

Hulkenberg's best lap in one minute and 44.395 seconds left him 0.052 seconds clear of nearest rival and compatriot Nico Rosberg of Mercedes with another German four-time champion Sebastian Vettel of Ferrari in third place.

On a cold morning with intermittent rain, the session offered few clues to performance as the diesel spillage left the Sochi Autodrom circuit in a treacherous and slippy condition.

Few cars ventured out until the final 20 minutes when successive laps on slick tyres began to improve the conditions, but the final order was not representative.

Rosberg's Mercedes team-mate defending two-time world champion and current series leader Briton Lewis Hamilton was seventh quickest after a tentative session that saw him required to avoid the spinning Williams of Brazilian Felipe Massa at one stage and spin himself soon afterwards.

Mexican Sergio Perez was fourth in the second Force India ahead of Australian Daniel Ricciardo of Red Bull and Spaniard Carlos Sainz of Toro Rosso.

It's actually a Nico 1-2 in #FP1, with @NicoHulkenberg P1 and @nico_rosberg P2. Has there ever been a Nico 1-2 before?! #RussianGP

— MERCEDES AMG F1 (@MercedesAMGF1) October 9, 2015

First practice classification

1 Nico Hulkenberg (Germany) Force India - Mercedes 1min44.355
2 Nico Rosberg (Germany) Mercedes 1min44.407
3 Sebastian Vettel (Germany) Ferrari 1min44.986
4 Sergio Perez (Mexico) Force India - Mercedes 1min45.146
5 Daniel Ricciardo (Australia) Red Bull - Renault 1min45.233
6 Carlos Sainz Jr (Spain) Toro Rosso - Renault 1min45.488
7 Lewis Hamilton (Britain) Mercedes 1min45.691
8 Valtteri Bottas (Finland) Williams - Mercedes 1min45.746
9 Max Verstappen (Netherlands) Toro Rosso - Renault 1min46.203
10 Kimi Raikkonen (Finland) Ferrari 1min46.215
11 Jenson Button (Britain) McLaren 1min46.231
12 Felipe Massa (Brazil) Williams - Mercedes 1min46.333
13 Felipe Nasr (Brazil) Sauber - Ferrari 1min46.747
14 Fernando Alonso (Spain) McLaren 1min47.443
15 Pastor Maldonado (Venezuela) Lotus - Mercedes 1min48.006
16 Daniil Kvyat (Russia) RedBull - Renault 1min48.096
17 Jolyon Palmer (Britain) Lotus - Mercedes 1min49.094
18 Roberto Merhi (Spain) Marussia - Ferrari 1min52.994
19 Marcus Ericsson (Sweden) Sauber - Ferrari 1min54.272
20 Will Stevens (Britain) Marussia - Ferrari 1min58.254