Fourth and fifth-quickest on the end-of-day timesheets were the two McLaren-Mercedes' of test drivers Pedro de la Rosa and Gary Paffett, the pair winding up just over half a second apart after completing respectively 65 and 78 laps in cars fitted with slick tyres and modified to simulate 2009 levels of aerodynamic downforce. De la Rosa focussed on the KERS-equipped MP4-23K, whilst Paffett will run solo on day two.

Luca Badoer was sixth-fastest for Ferrari just behind Paffett, as the Prancing Horse echoed McLaren's programme of low downforce and slick rubber, with weights added to the cars to simulate the situation when KERS will be employed. The Italian tried out new components and began a lengthy engine and gearbox reliability programme that took up the entire day, whilst fellow tester Marc Gené concluded 13th-quickest in an unmodified F2008 as he looked at set-up options, covering just 33 laps to Badoer's 108. Both drivers will take to the circuit once again on day two.

Next in the running order was Robert Kubica in the BMW-Sauber, both the race-winning Pole and the Munich and Hinwil-based outfit's test driver Christian Klien driving interim F1.08B machines featuring a modified 2008 chassis with some of the bodywork complying to the 2009 regulations, with the latter's car also equipped with BMW's own KERS device. Both drivers experimented with different mechanical and aerodynamic solutions.

“We are gaining more and more experience with the KERS system,” commented tenth-placed Klien, who will relinquish the wheel to race driver Nick Heidfeld on day two, before taking over again from Kubica on the final day. “We still have a lot of work to do to fine-tune the system, though.”

Five-time consecutive World Rally Champion Sébastien Loeb lapped an eye-catching eighth-quickest on his maiden 'proper' run for Red Bull Racing, the Frenchman less than two tenths of a second shy of Kubica's best effort. Loeb has been invited to test by the energy drinks-backed squad as a prize for his record-breaking title success, and clearly demonstrated the benefits of his Silverstone shakedown run last week.

After spending most of the morning settling in and finding a good balance on the car, the 34-year-old was actually put to more 'serious' use in the afternoon, when he worked on evaluating Bridgestone's 2009-spec slicks and providing the team with valuable data. RBR new boy Sebastian Vettel will take over for the final two days.

Behind Loeb, the recently re-confirmed Nelsinho Piquet placed ninth for Renault as he concentrated on 2009 set-up and tyre work, and the Brazilian was joined by 23-year-old Giedo van der Garde, who drove the R28 for the first time as a reward for his World Series by Renault title success. The Dutchman completed 32 laps as he acclimatised to the car and adapted well to his new surroundings.

“It was a constructive day,” affirmed Piquet, “although obviously we are right at the very start of winter testing and the cars will be very different next year. Still, it's nice to get a feel for how things are going to be with the sort of set-ups we will be running next year and with slick tyres. The car felt quite different today with these new settings, but the track conditions were good, which helped us.”

“It was a great day,” enthused former Spyker F1 test driver van der Garde. “The last time I was in a Formula 1 car was over a year ago, so I had to get used to the speed of the car again.

“We improved every time we went out, working on getting a better set-up, and hopefully we can continue like this tomorrow morning. It's been nice to work with the team – they are a good bunch of people and I'm really enjoying the experience.”