Kimi Raikkonen went quickest in first practice for the Bahrain Grand Prix, with Ferrari team-mate Sebastian Vettel second at a baking hot Sakhir Circuit. Mercedes, meanwhile, focused on long runs with Nico Rosberg and Lewis Hamilton down in 15th and 16th place respectively.

With track temperatures exceeding 50 degree and the running conducted in blazing sunshine, the session was unrepresentative of the conditions that will hold sway during Sunday’s first night race of the season and as such the timesheet had a somewhat muddled look, with Toro Rosso’s Max Verstappen in P1 and McLaren’s Fernando Alonso in second place for a period midway through the 90 minutes.

After using the free set of medium tyres on offer in the first half hour, many teams left it until late in the session to bolt on a second set, with the Ferrari drivers among that group.

Vettel, who had earlier been restricted to the Ferrari garage for a long period following a power loss on his car, was sent back out in the final ten minutes of the session and with the temperatures falling, the German jumped to the top of the timesheet with a lap of 1:38.029. That was swiftly eclipsed by Raikkonen who moments later crossed the line in a time of 1:37.827, to edge his team-mate by 0.202s.

Valtteri Bottas was third for Williams with a lap of 1:38.390. That put marginally ahead of Toro Rosso’s Carlos Sainz who had also waited for more representative track conditions before bolting on fresh tyres for a late run that netted him a fourth-best time of 1:38.447. Daniel Ricciardo was fifth quickest for Red Bull Racing, while Verstappen slipped to sixth with his best lap of 1:38.504.

Alonso gave one side of the McLaren garage something to smile about, with his best time 1:38.598 remaining good enough for seventh place.

There was less to celebrate on Jenson Button’s side of the McLaren pit.  The Briton stopped at Turn 2 just as he was starting his first flying lap. The team later reported an electric problem and he remained stuck in the garage for the remainder of the session.

Eight place in the session went to another late improved, Sauber’s Felipe Nasr, who set a best time of 1m 38.628s. The top 10 order was completed by Red Bull Racing’s Daniil Kvyat and Williams’ Felipe Massa.

Having taken on a second set of tyres early in the session, both Nico Rosberg and Lewis Hamilton concentrated on long runs, with Rosberg emerging the quicker of the two with a time of 1:39.293, just over two tenths of a second quicker than his team-mate.

2015 Bahrain Grand Prix – Free Practice 1
1 Kimi Raikkonen Ferrari 1:37.827   13
2 Sebastian Vettel Ferrari 1:38.029 0.202 12
3 Valtteri Bottas Williams 1:38.390 0.563 23
4 Carlos Sainz Toro Rosso 1:38.447 0.620 14
5 Daniel Ricciardo Red Bull Racing 1:38.455 0.628 17
6 Max Verstappen Toro Rosso 1:38.504 0.677 22
7 Fernando Alonso McLaren 1:38.598 0.771 18
8 Felipe Nasr Sauber 1:38.628 0.801 17
9 Daniil Kvyat Red Bull Racing 1:38.661 0.834 17
10 Felipe Massa Williams 1:38.790 0.963 21
11 Sergio Perez Force India 1:38.793 0.966 15
12 Pastor Maldonado Lotus 1:38.842 1.015 23
13 Nico Hulkenberg Force India 1:39.187 1.360 20
14 Jolyon Palmer Lotus 1:39.283 1.456 31
15 Nico Rosberg Mercedes 1:39.293 1.466 23
16 Lewis Hamilton Mercedes 1:39.532 1.705 22
17 Marcus Ericsson Sauber 1:39.534 1.707 21
18 Will Stevens Marussia 1:42.973 5.146 12
19 Roberto Merhi Marussia 1:44.265 6.438 15
20 Jenson Button McLaren No time   2