Nico Rosberg went quickest in final practice in Sochi in a session that was halted by a heavy crash involving Toro Rosso driver Carlos Sainz.

Rosberg had just set his best time of the session, a lap of 1:38.561, on supersoft tyres, when Sainz appeared to lose control under braking on the exit of Turn 13 and after scraping down the barriers his car arrowed off at high speed into barriers at Turn 14.

With 25 minutes left on the clock the session was immediately red-flagged and as Sainz was slowly extricated from the wreckage of his Toro Rosso the signal came from race control that the session would not be restarted. The young Spaniard was eventually freed from his car and gave a positive thumbs-up as he was taken by ambulance to the medical centre for evaluation.

Prior to the accident the session had been one of frantic action as teams attempted to make up for the time lost in Friday’s two disrupted practice sessions.

When the lights went green to signal the start the session most drivers were straight into the action. Many teams split their programmes, with one driver emerging on the soft compound Pirelli tyres and the other using the option supersoft compound in order to gather as much data as possible in advance of qualifying. The exceptions were the Ferrari drivers and it was a full 15 minutes before Kimi Räikkönen and Sebastian Vettel took the track, the former on supersofts and the latter on the soft tyres.

Williams’ Valtteri Bottas was the early pace setter, with the Finn initially rising to the top of the order on the soft tyre but as the session approached the half way point Rosberg took over at the top with a lap of 1:38.941s that put him three tenths of a second clear of Bottas. The Finn’s Williams team-mate Felipe Massa was third, over 1.5s seconds back, with McLaren’s Jenson Button fourth ahead of Sauber’s Felipe Nasr.

Rosberg then improved at the top to a 1m38.561s with Force India’s Sergio Perez rising to third on the back of a lap of 1:39.616. His stay there didn’t last long, however, as Lewis Hamilton was also on a supersoft run and with his second flying lap on the option rubber he took third with a time of 1:39.363 to sit 0.802s behind Mercedes team-mate Rosberg and just over a tenth off Bottas in second.

Soon after the championship leader crossed the line the yellow flags were out for Sainz’s crash and they quickly turned to red to bring the session to a halt.

With Rosberg in P1 ahead of Bottas and Hamilton, fourth place went to Perez, with Massa fifth. Force India’s Nico Hulkenberg was in P6 ahead of Button, Lotus’ Pastor Maldonado, Fernando Alonso in the second McLaren and Nasr in P10.

2015 Russian Grand Prix – Free Practice 3
1 Nico Rosberg Mercedes 1:38.561 15
2 Valtteri Bottas Williams 1:39.287 +0.726 17
3 Lewis Hamilton Mercedes 1:39.363 +0.802 13
4 Sergio Perez Force India 1:39.616 +1.055 14
5 Felipe Massa Williams 1:39.875 +1.314 14
6 Nico Hulkenberg Force India 1:39.917 +1.356 14
7 Jenson Button McLaren 1:40.581 +2.020 12
8 Pastor Maldonado Team Lotus 1:40.767 +2.206 13
9 Fernando Alonso McLaren 1:41.200 +2.639 11
10 Felipe Nasr Sauber 1:41.229 +2.668 14
11 Daniil Kvyat Red Bull Racing 1:41.358 +2.797 15
12 Kimi Raikkonen Ferrari 1:42.297 +3.736 11
13 Romain Grosjean Team Lotus 1:42.371 +3.810 14
14 Marcus Ericsson Sauber 1:42.450 +3.889 14
15 Carlos Sainz Jr. Toro Rosso 1:42.683 +4.122 19
16 Sebastian Vettel Ferrari 1:42.686 +4.125 11
17 Max Verstappen Toro Rosso 1:43.089 +4.528 16
18 Daniel Ricciardo Red Bull Racing 1:43.347 +4.786 14
19 Roberto Merhi Manor 1:46.767 +8.206 19
20 Will Stevens Manor 1:47.249 +8.688 18