JEREZ - Nico Rosberg of Mercedes GP set the fastest lap before rain slowed the 10-car field at a Formula One test session yesterday.
Rosberg, who will partner Michael Schumacher at the former Brawn GP team this season, set a fastest lap time of 1 minute, 20.927 seconds from 57laps around the Jerez Circuit.
"The car felt very good today. Compared to Valencia, where I was sitting too low which affected my visibility and the set-up wasn't perfect, today I felt really comfortable and I could push," Rosberg said. "The rain is a little frustrating but the car feels good to drive and that's what's important."
Toro Rosso's Sebastien Buemi was just over one tenth of a second back, ahead of Nico Hulkenberg of Williams and Ferrari driver Fernando Alonso, who was nearly two seconds back.
Sauber driver Kamui Kobayashi was fifth ahead of defending F1 champion Jenson Button of McLaren, who finished in front of Tonio Liuzzi as the Italian driver unveiled the Force India car.
"Today was definitely a good beginning to our testing program," Liuzzi said. "It was mainly about getting comfortable in the car, running through the systems."
Red Bull, which finished second to Brawn in the championship last year, was ninth as Mark Webber drove the new RB6 car for the first time.
Webber experienced an oil leak early on which led to a precautionary engine change, and the wet conditions kept the Austrian team from really getting going.
Virgin Racing was the first rookie team at the testing session, with Timo Glock placing last with a best time of 1:38.734 from five laps.
The British team was restricted to installation runs as it worked overnight to install new parts.
"Sadly, that meant we missed the dry-window, and we are not at a point where it is worth risking the car in wet running," technical director Nick Wirth said.
"As a result, we've kept things sensible and worked through the job list to prepare the car for tomorrow."
Russian driver Vitaly Petrov was eighth for Renault.
