The opening day of testing at Jerez belonged to Sebastian Vettel, who beat his rivals by over a second.
For the first time in pre-season testing, eight F1 teams were out in force in their new 2009 challengers. It was Red Bull, though, who proved to have the early upper hand.
On a day that was interrupted with a mid-day rain shower, Vettel posted an impressive 1:19.055 in his Red Bull racer, easily outpacing the Ferrari of Felipe Massa by almost 1.3s.
Massa's day, though, wasn't without problems as an off-track excursion for the Brazilian saw him sidelined for part of the afternoon.
Toyota test driver Kamui Kobayashi was another who impressed with his turn of pace, putting his TF109 up into third place. "This morning was my first real chance to try out the TF109 in dry conditions," said the Japanese driver.
"From the first run the car felt easy to drive so we were able to get straight into our programme of aero work. It certainly feels like a step forward from last year.
"The shower interrupted our afternoon but we still made it through our programme. Overall it went well so this was a good day of testing for us."
Fourth place went to Williams driver Nico Rosberg, who found himself just over two seconds off the pace while Robert Kubica was a further 0.1s back. The BMW driver, though, managed just 47 laps due to a precautionary engine change after sensors indicated there was a problem with his BMW power unit.
"Unfortunately I couldn't drive as many laps as planned. In the afternoon the session was interrupted by five red flags and the changing weather," said Kubica. "Because of this I expect a very busy day tomorrow."
Giancarlo Fisichella, putting the new Force India VJM02 through its paces, finished an admirable sixth, ahead of McLaren's Pedro de la Rosa and Renault's Nelson Piquet.
Piquet's day, however, was once again hampered by the reliability problems that have been plaguing Renault."We had a few issues with the car today which limited our mileage, but we still managed to evaluate some of the new parts we brought to this test," he said.
"The track was improving throughout the day as we had a lot of cars running and so it should get better and better throughout the week.
"Looking ahead to tomorrow, the priority is to get more miles under our belt - the weather should be similar so hopefully we will get another dry day."
1 S. Vettel Red Bull 01:19.055 87 laps
2 F. Massa Ferrari 01:20.330 63 laps
3 K. Kobayashi Toyota 01:20.699 79 laps
4 N. Rosberg Williams 01:21.171 71 laps
5 R. Kubica BMW 01:21.292 47 laps
6 G. Fisichella Force India F1 01:21.584 31 laps
7 P. de la Rosa McLaren 01:21.831 94 laps
8 N. Piquet jr. Renault 01:22.011 52 laps
Source : Planet F1