Michael Schumacher brought the Jerez test to a conclusion by posting the fastest time of the year, beating the previous best time, posted by Heikki Kovalainen yesterday, by 0.221s. On the final day of a four-day test at the Spanish track, the German was over a second quicker than his nearest rival, Jacques Villeneuve.

Schumacher was once again joined by Luca Badoer as Ferrari concentrated on development of aerodynamic and mechanical components, as well as evaluation of various types of Bridgestone tyre for the forthcoming French Grand Prix.

BMW continued to show good form, even if the aesthetics of its aerodynamic appendages leaves a lot to be desired.

Both Villeneuve, who ran with the 'fins' today, and Robert Kubica had a mixed programme, consisting of tyre and aero testing. They tried out several new parts which according to the team delivered "very promising results".

In the afternoon, the focus was mainly on tyre testing in view of the German Grand Prix at Hockenheim. The drivers evaluated different compounds and casings.

"Today did not run as smoothly as yesterday because we had to change out engines on both cars," admitted Toyota test team manager, Gerd Pfeiffer. The Japanese team had Ralf Schumacher and Jarno Trulli on duty.

"We were running pretty hard and working on specific test items," said Pfeiffer, "so these changes were expected, yet we lost some time during the day. Nevertheless, we were able to complete the preparations for Magny-Cours and made our tyre choice based on the data from today and yesterday. In two weeks time we test here again in Jerez and we will only be concentrating on tyres for the coming races, as this will be the last test before the summer break."

"It's been an extremely two hot days of testing for me and the guys in the garage," admitted Schumacher. "It's not so much a problem when I am driving because the wind cools you down - but it's hard when you're in the garage as the heat is unbearable, so the guys did an outstanding job in these conditions. We don't find this kind of heat everywhere we go, but it's good to test in extreme conditions because they give us a chance to learn things particularly on cooling, tyre wear and degradation. Besides this, we mainly concentrated here on tyre testing for next week's Grand Prix."

"It was a long hot day in the car today," added Trulli. "I tried to work on long runs in the morning to test the tyres for Magny-Cours, but my engine needed to be changed out and therefore I had to do them in the afternoon. Other than that, I did some general set-up work. I am really starting to get a clear understanding of the car now. Everything is slowly getting better- the tyres, the chassis, the set-up. Overall, the team is still working hard to work on the reliability of the car but I am sure that we will be able to end the season on a high note. It just takes patience."

Christian Klien was Red Bull's sole representative, the Austrian finishing seventh quickest, over 3s off the pace.

"We completed our tyre programme, in itself an achievement with just one car, and the new cooling package appears to be a definite improvement, which should bring some performance advantage at higher temperatures," said chief test engineer, Ian Morgan. "Our times are not really that representative, as Jerez is a very temperature-sensitive track, with fast times coming in the morning, when we were twice sidelined with car problems."

Propping up the timesheets was Mark Webber in the WilliamsF1, however, the Australian had a torrid time causing two red flag periods, one following an 'off', the other due to a mechanical failure.

"Mark had an accident in the morning," admitted test team manager Mike Condliffe, "fortunately he was fine but the left front of the car was damaged and therefore needed re-building before he was able to return to the track to continue an aero evaluation programme. Towards the end of the session, we completed the tyre selection test that we started earlier in the week."

"We are continuing an aggressive programme of engine development through the season," Cosworth's Sean O'Mahoney. "As such, at this week's Jerez test we tested some upgraded engine parts and ran extended engine duty above the normal race weekend mileage. The drivers were positive about the engine performance so we are looking forward to the race at Magny-Cours next weekend."

Eight teams return to Jerez later this month for a four-day test which begins on Tuesday 18 July, the last major test before the 'Summer break'.