Felipe Massa topped the times on the third morning of Formula 1 testing at Jerez, as he set the fastest time of the week so far.
The Ferrari driver, who will hand over to Pedro de la Rosa for the final day of running, became the first driver to lap under 1m18s this week.
Massa posted a 1m17.879s during a short run on the soft tyre, and then went only marginally slower on a similar run shortly after.
That left the Brazilian more than one second clear of Nico Rosberg, who had a busy morning as Mercedes made up for the time it lost on Monday and Tuesday.
Late improvements from Force India simulator driver James Rossiter and Jenson Button moved them up to third and fourth just before the halfway mark of the day, while world champion Sebastian Vettel was fifth after his first morning in the Red Bull RB9.
Jean-Eric Vergne, Esteban Gutierrez and Valtteri Bottas all got their first track action of 2013, as did 2007 world champion Kimi Raikkonen.
The Finn, who moved up to fourth fastest just before 1pm local time, had a quiet morning as the team focused on getting him comfortable in the car.
Charles Pic also spent the first part of his day getting settled in with Caterham, and the Frenchman caused the only red flag of the morning when his car came to a stop shortly after leaving the pits.
Pos Driver Team Time Laps 1. Felipe Massa Ferrari 1m17.879s 49
2. Nico Rosberg Mercedes 1m19.004s +1.125 69
3. James Rossiter Force India 1m19.303s +1.424 32
4. Kimi Raikkonen Lotus 1m19.539s +1.660 23
5. Jenson Button McLaren 1m19.603s +1.724 28
6. Sebastian Vettel Red Bull 1m19.676s +1.797 46
7. Jean-Eric Vergne Toro Rosso 1m19.707s +1.828 46
8. Esteban Gutierrez Sauber 1m19.995s +2.116 61
9. Valtteri Bottas Williams 1m21.578s +3.699 58
10. Max Chilton Marussia 1m23.938s +6.059 27
11. Charles Pic Caterham 1m25.365s +7.486 28
All Timing Unofficial
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