Mercedes remained on top of the Jerez timesheets on Thursday, courtesy of driver Nico Rosberg, but it was Lotus’s Romain Grosjean who was the fastest of those running in 2012 machinery. Grosjean set a best time of 1m 18.419s in the E20, as this week’s multi-team test continued in Spain. 

Defending 2011 world champion Sebastian Vettel was third quickest in the Red Bull ahead of McLaren’s Lewis Hamilton and Toro Rosso’s Jean-Eric Vergne. Vettel, Hamilton and Vergne were all behind the wheels of their respective teams' 2012 cars for the very first time.

Sauber’s Sergio Perez took the sixth slot in the C31, while Ferrari's Fernando Alonso was seventh in the Scuderia’s F2012. Alonso continued where team mate Felipe Massa had left off on Wednesday, gathering data. Alonso covered 67 laps, despite an interrupted morning caused by a hydraulic problem.

Bruno Senna was eighth on his first outing for new team Williams, ahead of Caterham’s new third driver Giedo van der Garde. Completing the day’s line-up was fellow reserve Jules Bianchi, who had completed just two laps when a collision with a tyre wall brought his - and Force India’s - day to a premature end. With the team now waiting for spare parts to arrive the accident meant race driver Nico Hulkenberg’s first taste of the new VJM05 was postponed until Friday.

Unofficial Thursday test times from Jerez:
1. Nico Rosberg, Mercedes*, 1:17.613, 118 Laps
2. Romain Grosjean, Lotus, 1:18.419, 117 Laps
3. Sebastian Vettel, Red Bull, 1:19.297, 96 Laps
4. Lewis Hamilton, McLaren, 1:19.464, 80 Laps
5. Jean-Eric Vergne, Toro Rosso, 1:19.734, 79 Laps
6. Sergio Perez, Sauber, 1:19.770, 48 Laps
7. Fernando Alonso, Ferrari, 1:20.412, 67 Laps
8. Bruno Senna, Williams, 1:21.293, 125 Laps
9. Giedo van der Garde, Caterham, 1:23.324, 74 Laps
10. Jules Bianchi, Force India, no time, 2 Laps
* 2011 car

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