Mercedes set the early pace in Bahrain

Lewis Hamilton tops first free practice session, with team-mate Rosberg second ahead of Ferrari’s Fernando Alonso.

Lewis Hamilton began his Bahrain Grand Prix weekend in the style he concluded last weekend’s race in Malaysia, the Briton setting the pace ahead of team-mate Nico Rosberg.

Ferrari’s Fernando Alonso was third-fastest, despite a bizarre pit lane glitch in which the Spaniard’s car was fitted with three medium compound Pirellis and one soft compound tyre.

Hamilton bookended the session with fastest times on medium compound tyres, running a tenth quicker than Rosberg in the opening half hour – on the extra set of prime tyres teams have access to during this period – and then by just over two tenths at the end of the session

Following the pit lane error that saw him released with mismatched tyres, Alonso climbed the order to record best time of the session four tenths down on Hamilton. He was followed, a tenth further back, by Force India’s Nico Hulkenberg, the German renewing the hostilities that have led to fascinating duels in the opening two races of the season.

Fifth spot on the timesheet went to McLaren’s Jenson Button. The Briton, who will start his 250th grand prix on Sunday, finish a tenth of a second clear of the second Ferrari of Kimi Raikkonen. Button’s team-mate Kevin Magnussen was seventh, ahead of Toro Rosso’s Daniil Kvyat, who ended up 1.5s off the fastest time. Red Bull Racing’s Sebastian Vettel finished the session in 10th place and almost 1.9s adrift of Hamilton’s benchmark.

A number of reserve drivers got their first outings of the season during the session. Brazil’s Felipe Nasr took over Valterri Bottas’ Williams and finished the session in 13th place, 2.5s down on the afternoon’s best time.

Sauber's Giedo van der Garde, meanwhile drove Esteban Gutierrez's Sauber to 18th spot on the timesheet and Robin Frijns was 21st fastest for Caterham in Kamui Kobayashi's CT05.

2014 Bahrain Grand Prix – Free Practice 1 Result
1 Lewis Hamilton Mercedes 1:37.502 14
2 Nico Rosberg Mercedes 1:37.733 0.231 13
3 Fernando Alonso Ferrari 1:37.953 0.451 17
4 Nico Hulkenberg Force India 1:38.122 0.620 10
5 Jenson Button McLaren 1:38.636 1.134 16
6 Kimi Räikkönen Ferrari 1:38.783 1.281 12
7 Kevin Magnussen McLaren 1:38.949 1.447 15
8 Daniil Kvyat Toro Rosso 1:39.056 1.554 24
9 Sergio Perez Force India 1:39.102 1.600 21
10 Sebastian Vettel Red Bull Racing 1:39.389 1.887 16
11 Felipe Massa Williams 1:39.533 2.031 11
12 Jean-Eric Vergne Toro Rosso 1:39.862 2.360 26
13 Felipe Nasr Williams 1:40.078 2.576 14
14 Daniel Ricciardo Red Bull Racing 1:40.406 2.904 19
15 Adrian Sutil Sauber 1:40.652 3.150 20
16 Pastor Maldonado Lotus 1:40.793 3.291 31
17 Jules Bianchi Marussia 1:40.889 3.387 20
18 Giedo van der Garde Sauber 1:40.913 3.411 20
19 Romain Grosjean Lotus 1:41.036 3.534 24
20 Max Chilton Marussia 1:41.794 4.292 20
21 Robin Frijns Caterham 1:42.417 4.915 35
22 Marcus Ericsson Caterham 1:42.711 5.209 21