Nico Hulkenberg tops shortened practice in Sochi

Nico Hulkenberg topped the timesheets in Sochi as the opening practice session for the Russian Grand Prix descended into farce after an early diesel spill.

The Force India driver produced the fastest lap in the final seconds of the session to go 0.052 seconds faster than Mercedes' Nico Rosberg in a competitive last 15 minutes.

However, the day started in comical scenes as the track sweeper designed to prepare the surface spilled its fuel onto the track " making conditions hazardous for the drivers.

The session was immediately yellow flagged for 30 minutes and the cautious paddock remained in their garages for another 20 minutes before the first timed lap was recorded.

All 20 drivers had completed installation laps after practising their starts in the pit lane, but none registered a time until Fernando Alonso finally put a marker down with a slow lap of 2:00.736.

With 15 minutes remaining, only a handful of drivers had set a time, but improving track conditions prompted some late action.

Hulkenberg and Williams' Valtteri Bottas were immediately towards the top of the timesheets, while Felipe Massa and championship leader Lewis Hamilton " who was seventh fastest " both spun as they tried to get to grips with the conditions.

Rosberg had fewer problems as he went quickest late on, but he was denied top spot at the end of the 90-minute session as Hulkenberg clocked one minute 44.355 seconds to snatch top spot.

1. Nico Hulkenberg (Force India) 1:44.3552. Nico Rosberg (Mercedes) 1:44.4073. Sebastian Vettel (Ferrari) 1:44.9864. Sergio Perez (Force India) 1:45.1465. Daniel Ricciardo (Red Bull) 1:45.2336. Carlos Sainz (Toro Rosso) 1:45.4887. Lewis Hamilton (Mercedes) 1:45.6918. Valtteri Bottas (Williams) 1:45.7469. Max Verstappen (Toro Rosso) 1:46.20310. Kimi Raikkonen (Ferrari) 1:46.215