“Based on the results of the last test in Barcelona we changed the mechanical set-up of the car,” related Heidfeld, who looked at suspension and aerodynamic settings in particular, and will be joined by team-mate Robert Kubica in place of Klien on Wednesday. “It looks like we are moving in the right direction.”
Seventh on the final timing screens was Williams' Kazuki Nakajima, who will head into his second full campaign in the top flight in 2008. The 23-year-old Japanese ace concentrated his efforts on set-up work and slick tyre development in preparation for next season.

“Heavy rain showers interrupted the majority of today's session,” reported the Grove-based outfit's test team manager Dickie Stanford, “so we spent much of the time in the garage. During the time we did get on-track, Kazuki ran through set-up configurations on the FW30B and testing the slick tyres. Nico [Rosberg] joins us for the last two days of the test and will continue work on our development programme.”

Nelsinho Piquet, finally, wound up eighth-fastest in the sole Renault present, the young Brazilian making the most of the morning's dry running to carry out further slick tyre evaluation whilst simulating a 2009 car set-up. The team was also able to put some more mileage on the engine in preparation for the three-race rule that will come into force next season.

“It has been a good day,” remarked Piquet, who covered a marathon 124 laps before he hands over to team-mate Fernando Alonso for the Spaniard's return to the cockpit on Wednesday for the first time since the Brazilian Grand Prix. “I did lots of laps and we completed what we needed to in terms of putting mileage on the car, despite the rain showers.

“The cool conditions meant that the track conditions were quite cool throughout the day, but the grip was good, which has given us some more valuable data about the tyres.”

“It's been a positive first day here in Jerez,” agreed the Régie's chief test engineer Christian Silk. “Nelson did a good job completing a lot of laps, so we've been able to achieve the main targets for the day, which is always encouraging.

“The conditions were quite cold today and the weather was quite changeable which meant we had to keep adapting out programme, but overall we can be happy with our day's work.”

To see the testing times in full, click here