For the second consecutive day, McLaren's Pedro de la rosa was the pace-setter at Jerez.

Air temperatures reached over 30 degrees at the Spanish track and track temperatures were reached over 40 degrees Celsius.

de la Rosa, who was once again partnered by Englishman Gary Paffett, completed 117 laps on his way to posting a best time of 1:17.782, as the Woking team continued yesterday's programme of tyre selection for the French Grand Prix, with evaluation for Hockenheim also included.

The Spaniard's main focus was the engine development programme, as his MP4-21 was fitted with an upgraded Mercedes-Benz V8 engine.

The Renault duo of Heikki Kovalainen and Fernando Alonso were second and third quickest, the reigning World Championship having his first experience of the 'C' spec (upgraded) RS26 powerplant that Giancarlo Fisichella used at Indianapolis.

Rubens Barrichello, taking over from James Rossiter, joined Anthony Davidson, as Honda looks for a significant improvement at Magny Cours.

Rubens began the day with some early set-up runs before working through an aero evaluation. He started a chassis set-up programme in the early afternoon, however a spin at turn ten resulted in some minor damage to the rear of the car interrupting his running for a short time.

The Brazilian was able to go back out fairly quickly, however an engine failure late in the afternoon ended his running slightly earlier than planned.

Davidson spent the day working through a comprehensive chassis set-up programme, alongside a tyre evaluation looking at options for the forthcoming races.

Jenson Button will join the test tomorrow, taking over his fellow-Englishman.

Alex Wurz was fifth quickest, the Austrian, once again being WilliamsF1's sole representative.

"Over the course of the session, we predominantly worked on aero evaluations and tyre comparisons," said test team manager, Mike Condliffe. "Towards the end of the day, Alex also carried out some brake work. Altogether, we've enjoyed a very productive day, despite a high number of interruptions due to red flags."

BMW caused a stir, what with Sebastian Vettel (right) having his second ever F1 outing and Robert Kubica's car sporting strange fin-like aerodynamic devices on either side of the monocoque, which looked as though they were there to support a TV monitor. If Honda’s Geoff Fry was unhappy with the legality of the German team's rear wing in Canada, he'll have kitten when he sees this.

Kubica who mainly concentrated on evaluating various new aerodynamic parts, also did a tyre test for Michelin, but was forced to finished early following a mechanical failure.

Vettel, who turned 19 just two days ago, completed 83 laps without any problems, posting a best time just 1.8s off the pace.

"This was obviously a special opportunity for me," said the youngster, "but I just tried to take it easy and concentrate on my job. The whole day went really well. I was able to complete many laps without any problems.

"I learned a lot, particularly on tyres," he added. "That's a very complex issue in Formula One, because they change a lot over a run and one has to adapt the driving style. It's clear that I cannot exploit the whole potential of the car yet, but that seems to be a matter of time. I'm happy with the day."

Tomorrow, Robert will continue to drive while Jacques Villeneuve will take over from Vettel. Nick Heidfeld, who was initially scheduled to drive, changed his plans due to a muscle twinge in his neck after his crash in Indianapolis.

On Toyota's first day of testing, Ricardo Zonta was joined by Olivier Panis. Although the test programme this week will focus mainly on preparations for the coming race at Magny-Cours, today's running concentrated on general tyre work and set-up.

"This was the first time we tested the TF106B in Jerez and we have a long agenda here," revealed test team manager, Gerd Pfeiffer. "In addition to race preparations for Magny-Cours, we are also testing various new parts in the car and gaining data on different tyre constructions. Today's testing was to gain more general data that will be used for future races, whereas tomorrow our race drivers will concentrate on specific set-up items for the next race."