Herbert and de la Rosa begin testing duties

Herbert, who retired from Grand Prix racing at the end of last year, signed as development driver for Tom Walkinshaw's Arrows team last month, while de la Rosa has taken refuge with Jaguar Racing after Walkinshaw replaced the Spaniard with Enrique Bernoldi.

Although Herbert has been brought in to help develop this year's AMT-powered A22, today's running was confined to last year's car as both examples of the 2001 challenger are en route for Malaysia. The popular Brit is adamant that his development role is not a back door to a Grand Prix racing return.

De la Rosa however, has signed with the Big Cat with an express view to getting a race seat in 2002. In Australia, Jaguar Racing overlord Niki Lauda reiterated that de la Rosa was certain to race next year, so the 30-year-old's presence in the team is helping to increase the pressure on current drivers Eddie Irvine and Luciano Burti.

The duo were greeted with a wet Silverstone track this morning and as a result did not complete much running during the first session of day one of three.

Both were hindered by seat fitting problems and a replacement is being made for Herbert overnight, while de la Rosa said that his seat is "still not comfortable yet."

Benetton and Williams are also present at the Northamptonshire track with their respective test drivers, Mark Webber and Marc Gene. Jaguar was the only team to have a 2001-spec car at the track - in the hands of de la Rosa - and also to have two cars running, with second test driver Tomas Scheckter driving an interim R1B.

Autosport.com will bring you all the times and a full report of the action at the end of the day.