Formula 1: De la Rosa in action after Burti walks out

Jaguar Racing's Spanish test driver Pedro de la Rosa has been handed his drive earlier than expected after Luciano Burti left the team.

Burti is joining the Prost team after they axed Argentinian Gaston Mazzacane.

The changes will come into effect for next week's Spanish Grand Prix in Barcelona, the fifth round of the 17-race season.

Mazzacane and Burti's places have been the subject of speculation virtually since the opening race of the season and intensified in last week's San Marino Grand Prix.

Burti was testing for Jaguar at Silverstone on Thursday but was due to spend the last hour of the session behind the wheel of a Prost.