Irvine eventually finished 15th and team-mate Pedro de la Rosa was 13th as the Milton Keynes-based team had to change their planned test programme on the R3B.

‘‘We were very limited in what we could do today,’’ said Irvine, who has struggled for pace after scoring three fortunate points in the season opener in Australia last March.

‘‘We still have a fair way to go before we begin drawing any conclusions, but the early signs are encouraging, albeit somewhat diluted by the horrendous weather conditions.

‘‘Hopefully we will find out what the true situation is tomorrow.’’

Team chief Niki Lauda said: ‘‘Not an ideal day to begin preparing for the weekend ahead - but this is Silverstone after all!

‘‘The heavy rain has not lent itself well to our planned programme. The drivers have, however, reported some encouraging feedback in certain areas of the car but until we conduct a full programme the results from the new package remain inconclusive.’’

Jaguar tested the new car for the first time in Barcelona last week having been forced to work on revising the R3 after a serious aerodynamic flaw was discovered in pre-season testing.

The Ulsterman who has spent much of the season near the back of the grid has said this weekend’s race will be a key to deciding his F1 future.

Irvine could quit the sport when his three year £18million deal with Jaguar ends this season if there is no promise of a much-improved car in 2003.