The rain certainly hit the Spanish plain today, as persistent rain showers caused problems at Jerez, deep in the heart of the country's Sherry region.

Sauber's Felipe Massa topped the timesheets, though due to the conditions he was unable to complete as many laps as had been hoped for. Jacques Villeneuve takes over from the Brazilian on Thursday and Friday.

"The mixed weather was not very helpful today and under such conditions I normally wouldn't say that it was a positive day," admitted Giampaolo Dall'Ara. "But even though we were not able to run as many laps as planned, we could still learn a lot and the day was finally productive as the quick lap times show. We further adapted the car to the Michelin tyres and did some aerodynamic data validation as well as worked on the mechanical set-up of the C24. We have scheduled more aerodynamic tests and will continue to work with Michelin."

Second quickest was Jarno Trulli, who was joined by 2005 teammate Ralf Schumacher. The German was one of several drivers to go off, the former WilliamsF1 star having his 'moment' at Turn 2 in the morning. Although his car was damaged, it was repaired in time for the afternoon session.

Although teammate Trulli was 1.7s off Massa's time, this was because the Brazilian was on track at the optimum moment, rather than the Swiss team suddenly finding a massive performance increase. Trulli was running the latest-spec engine as the Japanese team experimented with various aerodynamic solutions.

Mark Webber, took full advantage of the conditions, working on wet tyre testing for Michelin. He also worked on electronics and reliability running. The Australian completed the most laps today (106), finishing third quickest.

Mark was joined by Nick Heidfeld, who despite the conditions gave a good account of himself as he familiarised himself with the WilliamsF1 BMW FW26C. The German, who focussed on traction control evaluations, completed 101 laps. Nick will remain on duty tomorrow, when he will be joined by Antonio Pizzonia.

"Even though the weather was mainly wet today, we completed a combined total of 917kms on the two FW26C interim cars," said Sam Michael, "which is a good achievement at such an early stage with the new rear end.

"Mark worked on wet tyre testing for Michelin, electronics and reliability running. He was joined today by Nick Heidfeld who did a great job in the other car."

Fourth quickest was Enrique Bernoldi, who was joined by Takuma Sato, in the 'concept car', and two F1 hopefuls, Alan van der Merwe and Adam Carroll. Bernoldi was running the 2004, albeit with 2005 'downforce levels'.

Luca Badoer was fifth fastest, despite going off at the same corner as Ralf Schumacher. The Italian was joined by Marc Gene, as they worked on a development programme of Bridgestone tyres and new components.

Vitantonio Liuzzi was the quicker of the two Red Bull drivers, despite two offs. The Austrian drove the (Jaguar) R5 chassis, while Liuzzi was assigned the R5C.

Christijan Albers and Robert Doornbos were on duty for Jordan, both drivers running an 'interim' chassis.

Testing continues tomorrow (Thursday), when McLaren and Renault will join in the fun.

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