A vehicle dumped diesel fuel on the track, which caused Free Practice 1 to be delayed 30 minute, and left the track slick even after the cleanup.
Ericsson and Alonso were the first out on the 3.637-mile (5.853-km) 18-turn (12 right and 6 left) Sochi street track for what was now a 60-minute FP1. Officials declared that the session was "wet" due to the chemicals used for the spill so the drivers were on the intermediate or full wet Pirelli tires.
Alonso, first on the slicks, posted the first lap time: 2:00.736. He then improved that to a 1:56.327 and then a 1:53.854 before spots of rain were felt.
But the rain forecast for FP2 held off, and the drivers got some fast laps in during the last 10 minutes of the session with Nico Hulkenberg leading the way with Mercedes power on a lap of 1:44.355s. The times are meaningless as they were a full second off the best FP1 time from Mercedes' Nico Rosberg a year ago and last year's tires were harder.
It was Rosberg second best, finishing just 0.052s adrift, again with Mercedes power, with Sebastian Vettel third quickest in his Ferrari, 0.631s off the pace.
Results Practice 1
|1||Nico Hulkenberg||Force India/Mercedes||1:44.355||0.000s||11|
|4||Sergio Perez||Force India/Mercedes||1:45.146||0.791s||11|
|5||Daniel Ricciardo||Red Bull/Renault||1:45.233||0.878s||10|
|6||Carlos Sainz||Toro Rosso/Renault||1:45.488||1.133s||13|
|9||Max Verstappen||Toro Rosso/Renault||1:46.203||1.848s||13|
|16||Daniil Kvyat||Red Bull/Renault||1:48.096||3.741s||9|