Pedro de la Rosa completed Team McLaren Mercedes' first test session of 2006 at the Circuito de Jerez in Spain today at the wheel of an interim MP4-20. The track was artificially dampened to create wet conditions for Michelin tyre testing, this allows the teams and Michelin to control the amount of water on track and therefore quantify the data gained.

Running commenced at 10am with just Rubens Barrichello and Christian Klien on track alongside Team McLaren Mercedes, and Pedro covered over 450kms in total. Pedro was first on the timesheets today, having also put in the fastest time of the week on Wednesday with a 1m16.504.

Today's wet test was day four of this week's session at the Jerez track for Team McLaren Mercedes. The focus has been tyre development work with Michelin, with Pedro and reigning DTM Champion Gary Paffett driving two MP4-20s. The team was using the V10, because engine production is focused on the FO108S V8 for the MP4-21, which has different mountings from the one used in the MP4-20. The 2006 Challenger, the MP4-21, will have his test debut later this month.

Wednesday saw Pedro top the timesheets with the quickest time of the week, despite a minor software problem on his installation lap. This was resolved quickly by the test team and both Pedro and Gary, in his first official test for the team, had busy days completing nearly 750km between them.

The good mileage continued the following day, with the only stoppage being for Pedro 30 minutes from the end with an engine failure, on an engine that had covered close to 1,500km already.

Friday's session was badly affected by red flag stoppages across the field of ten runners, with Renault, Honda, BMW Sauber, Williams and Red Bull Racing also in attendance at Jerez. Nearly twice as much time during the day was spend under red flag conditions, with no action taking place, than green. Then heavy rain fell towards the end of the session, which ended the day early.

Pedro was present for all four days of the test and completed 291 laps and 1,280 km in total respectively. Gary was on track for three days and completing approximately 950km over 215 laps.

Pedro de la Rosa: "We have had a constructive session this week in Jerez, particularly with our work with Michelin. We have been completing sections of the pre-season tyre programme and we are getting a good understanding of performance and how to maximise this with Michelin. Today's controlled wet test has also been beneficial. Because we are in control of the amount of water on track; it allows us to apply appropriate compounds and set-ups that we can fully quantify. It is not possible to conduct this type of testing when it is raining, such as yesterday afternoon. We have had a few minor glitches with software, which have led to a couple of stoppages on track for me and Gary. However this is because in addition to tyres, software is currently another area of focus and development, and this is only to be expected when you are testing."

Gary Paffett: "It has been a really interesting week for me, to be testing for the first time as an official Team McLaren Mercedes test driver. We had solid test sessions with good running on Wednesday and Thursday, completing my programme on both days. Obviously until the MP4-21 is released there is a big focus on tyre testing with Michelin and by covering good distances every day we are getting some good feedback. Friday was a bit frustrating with all the stoppages, two of which were myself with a couple of small electronic software issues, however that is testing, and it was generally a good week overall."