On the final day of testing at Jerez, it was Lewis Hamilton who topped the timesheets, at least in terms of 2009 contenders. Quickest overall was Sebastien Bourdais as Toro Rosso ran its 2008 car for the last time.

For Toro Rosso it was a bit of an emotional day as the team bid farewell to the STR3, the car with which it enjoyed so much success last year, most notably the memorable win at Monza.

In good conditions which saw temperatures reaching 30 degrees, Sebastien Bourdais had the honour of driving the car for the last time, working on a qualifying simulation programme with three different compounds of tyre, while also carrying out an evaluation of the front and rear suspension.

A reliability validation of the Ferrari 056 engine was also completed, with the unit doing even more laps than expected. Unfortunately, a minor mechanical problem meant the day ended an hour ahead of schedule, but nevertheless, the day's full programme was completed.

"It's been a while since I've driven and it's good to get back in the groove," said Bourdais. "We are just continuing to evaluate tyres and understand how the slicks are working, as well as trying a few things on the geometry of the car. All in all, a useful working session."

Hamilton was quickest of the 2009-spec cars even though the Woking outfit was once again running a hybrid version of its 2008 rear wing. The ideal conditions allowed the team to continue putting some serious mileage on the new car, while time was also spent "finessing" the car's balance and set-up on slick tyres while also putting background miles on the KERS device - which has proved largely trouble-free during all four days of the test.

Having been the 'back marker' for much of this week's test, Renault moved up the timesheets on the final day, Fernando Alonso finishing third quickest, just 0.214s off Hamilton's pace.

For the French team, the main priority was to continue adding miles to the car while working on the KERS system and evaluating various development parts. The team concentrated on shorter stints in the morning before completing some long runs in the afternoon, along with set-up work.

Alonso had a productive day, completing 109 laps, which the team clams confirms the progress it has made this week.

"After doing so many laps with the car yesterday, we concentrated more on set-up work today to get a better understanding of the car and make it easier to drive," said the Spaniard. "Overall, we have to be very happy as we managed to do lots of laps and the car responded well to the set-up changes we made, so I think we've found some good solutions. Everyday the drivability of the car is improving and although we still have a lot of work to do before the start of the season, we are definitely moving in the right direction."

"A very good day's testing," added Christian Silk. "We've continued to make progress with the car and it ran well today which allowed us to get more mileage and check our reliability. We're continuing to make changes and the car is responding very well to those and so we've already found a good balance. Overall it's a positive end to the test for us."

Williams had Nico Rosberg and Kazuki Nakajima over the course of the day. The Japanese driver concentrating on practice pit stops and therefore failing to post a competitive time. Teammate Rosberg completed 71 laps, finishing fourth quickest overall, 1.491s off Hamilton's pace.