McLaren's Pedro de la Rosa was the quickest driver at Jerez on the second day of testing, however, since the Spaniard was running with a V10 engine, it means that Michael Schumacher (Ferrari) was, once again, quickest of the V8 runners.

The Woking outfit had both de la Rosa and Gary Paffett on duty, however, although the team ran with the new Mercedes V8 powerplant at the end of 2005, it has reverted to the (restricted) V10, claiming that this was scheduled because; "engine production is focused on the FO108S V8 for the MP4-21, which has different mountings from the one used in the MP4-20B".

According to the team: "The V8 on track programme will be continued once the MP4-21 starts testing. By the end of the final test in December 2005, over 6,000kms had been covered by the V8 engine".

The programme for the day, which will continue over the remainder of the week until Saturday, focused on tyre development work with Michelin.

The Spaniard had a minor software problem on his initial installation lap, which was resolved immediately and he continued with his programme. Both cars ran for the rest of the day with no further electronic or mechanical issues.

Michael Schumacher, again at the wheel of a V8 powered F2004, concentrated on development work in collaboration with Shell, while Luca Badoer, driving an F2005, fitted with a regulated power V10 engine, continued with the Bridgestone tyre programme he had begun yesterday.

Both drivers now head off to the Dolomites to take part in Ferrari's annual press get together at Madonna di Campiglio. Therefore, tomorrow (Thursday), Marc Gene will alternate between the F2004 and F2005.

Third quickest was Ricardo Zonta, who was joined by Ralf Schumacher and Jarno Trulli.

Fourth quickest was Fernando Alonso, while teammate, Giancarlo Fisichella continued with the R26.

At this early stage, the team's priority is simply to build mileage with the new chassis and engine package, without focusing on performance development. After completing several installation laps and short runs, Fisichella's programme therefore centred around long runs, which were only interrupted by red flags due to incidents involving other cars. His lap-times proved consistent, with both chassis and engine performing well.

In improved conditions relative to yesterday, with warmer track and ambient temperatures through much of the afternoon, Alonso completed an extensive tyre development programme with technical partner Michelin. Tomorrow, he will get his first taste of the R26 as Giancarlo takes over the tyre programme with last year's car.

"We had a slow start to the morning as we concentrated on installation laps and system checks," said Bob Bell, "but after these had been completed to our satisfaction, we continued building our mileage with the new car, culminating in two longer runs in the afternoon in spite of interruptions owing to red flags. These went very well, with Giancarlo's lap-times indicating the chassis is handling consistently while the V8 engine once again ran well.