Rosberg quickest in Bahrain FP2

Nico Rosberg followed up his Shanghai victory with another commanding performance in the second free practice session for the Bahrain Grand Prix.

As off-track controversy escalated amid news that Force India would miss the session because of concerns about its personnel travelling back from the circuit after dark, Rosberg emphasised Mercedes' Sakhir speed with a pacesetting 1m32.816s.

The German set that time just over half an hour into the afternoon, ending a busy spell in which the two Mercedes and Red Bull's Sebastian Vettel had been swapping the top spot.

When he set that lap, Rosberg went a full 0.8 seconds quicker than anyone else, and although that margin reduced, no one was able to topple the Mercedes.

Mark Webber ended up second for Red Bull, 0.446s down on Rosberg, and 0.263s ahead of his team-mate Vettel, who had a near-miss with compatriot Michael Schumacher near the end of the session.

Neither car was damaged, and Schumacher completed the day in fifth, a second off his pacesetting Mercedes team-mate.

The seven-time champion was sandwiched between the two McLarens, with Lewis Hamilton fourth and Jenson Button sixth - 0.9s and 1.4s off Rosberg respectively.

Sauber had an encouraging session, as Kamui Kobayashi and Sergio Perez took seventh and 10th, split by Fernando Alonso's Ferrari and Romain Grosjean's Lotus.

Force India's decision not to take part meant only 22 cars ran, with the Silverstone squad's crew instead getting an early start on preparing the cars for Saturday and qualifying before leaving the circuit.

There were myriad minor excursions over kerbs and run-off areas on the still-dusty track, but no major dramas, incidents or problems, with all the cars that ran completing between 25 and 35 laps.

Pos  Driver               Team                  Time               Laps
 1. Nico Rosberg          Mercedes              1m32.816s            35 
 2. Mark Webber           Red Bull-Renault      1m33.262s  + 0.446   26 
 3. Sebastian Vettel      Red Bull-Renault      1m33.525s  + 0.709   28 
 4. Lewis Hamilton        McLaren-Mercedes      1m33.747s  + 0.931   26 
 5. Michael Schumacher    Mercedes              1m33.862s  + 1.046   31 
 6. Jenson Button         McLaren-Mercedes      1m34.246s  + 1.430   28 
 7. Kamui Kobayashi       Sauber-Ferrari        1m34.411s  + 1.595   34 
 8. Fernando Alonso       Ferrari               1m34.449s  + 1.633   31 
 9. Romain Grosjean       Lotus-Renault         1m34.615s  + 1.799   32 
10. Sergio Perez          Sauber-Ferrari        1m34.893s  + 2.077   34 
11. Daniel Ricciardo      Toro Rosso-Ferrari    1m34.895s  + 2.079   29 
12. Felipe Massa          Ferrari               1m34.941s  + 2.125   29 
13. Kimi Raikkonen        Lotus-Renault         1m35.183s  + 2.367   33 
14. Jean-Eric Vergne      Toro Rosso-Ferrari    1m35.229s  + 2.413   26 
15. Pastor Maldonado      Williams-Renault      1m35.459s  + 2.643   38 
16. Vitaly Petrov         Caterham-Renault      1m35.913s  + 3.097   32 
17. Heikki Kovalainen     Caterham-Renault      1m35.968s  + 3.152   35 
18. Bruno Senna           Williams-Renault      1m36.169s  + 3.353   30 
19. Timo Glock            Marussia-Cosworth     1m36.587s  + 3.771   32 
20. Charles Pic           Marussia-Cosworth     1m37.803s  + 4.987   33 
21. Pedro de la Rosa      HRT-Cosworth          1m37.812s  + 4.996   28 
22. Narain Karthikeyan    HRT-Cosworth          1m39.649s  + 6.833   27