Minardi's Mark Webber put in an impressive performance on Friday when he tested for the Jaguar team in Barcelona. Webber was just three hundredths of a second slower than team regular Pedro de la Rosa, despite using a lower spec Cosworth engine.

Both men were at the wheel of the heavily revised Jaguar R3b, the car charged with reversing the team's fortunes in the remainder of the 2002 season. And after its first full day of track running, De la Rosa reported some very positive signs.

Webber's test was originally planned as part of Jaguar's routine preparations for 2003, but it also gave the team the opportunity to gather vital additional data on the new car. The Australian driver said he was immediately at ease in the R3b and pleased to have matched De la Rosa's pace.

"I did a seat fitting last Monday so my seat was comfortable, the cockpit area was okay and I had no problems with the pedal positions or anything," he said. "I enjoyed the test and it was very nice to be given the opportunity to be able to drive a different car.

"I am happy with the work I've done. The time I did doesn't look too bad compared to Pedro, especially as Pedro had a higher spec engine, so I am satisfied. The car is very different (to the Minardi PS02), but in Formula One™ from one car to another everything is so different anyway."

De la Rosa also reported key differences, in his case between the new R3b and its predecessor. It was the Spaniard's first taste of the revised car, after team mate Eddie Irvine completed just a handful of installation laps on Thursday.

Designed by Jaguar's new technical chief Guenther Steiner, the R3b features an all-knew aero package including a reworked nose-cone, barge-boards and undertray. And despite the team finishing bottom of Friday's time sheets, de la Rosa said improvements were immediately clear.

"It was very positive and we can see the car was getting better and better," he said. "We tried many things - all the possibilities like ride heights, dampers, suspension settings - and bit by bit we are basically learning.

"Right towards the end we changed the front wing session and it definitely made an improvement and the car is capable of going a lot faster. It is great for me and it is great for Jaguar.

"The car is definitely more stable under braking. It is less pitch sensitive in corners, so at least I know what the car is going to do when I enter a corner. It was very positive.

"If anything I would like to have done more running, as this is something we have been waiting for for a long time. We have had nothing new (in the way of major developments) since Melbourne and it's a big weight off our shoulders."

However, despite his optimism, de la Rosa insisted it was still early days and refused to make any rash predictions about Jaguar's chances for next weekend's British Grand Prix.

"It is only the first day of testing so you can't say how good it is and I can't say how good it will be at Silverstone," he added.

Jaguar have not scored a world championship point since Eddie Irvine finished fourth in the opening round of the season in Australia.