Hamilton sets 2009 cars pace at Jerez

But the Briton was shadowed by Red Bull's Sebastian Vettel, who finished just 0.001 seconds behind in the RB5, as the car continued to show its potential in only its fourth day of running.

Toro Rosso's Sebastien Bourdais, in his first test since he was confirmed for the 2009 season, posted the quickest time of the day in the 2008-spec car, finishing over two seconds ahead of Hamilton.

The McLaren driver, taking over from teammate Heikki Kovalainen, managed 93 laps at the wheel of the MP4-24 and was left pleased with his day's work.

"Today's test gave me the first opportunity to drive MP4-24 in warm, dry conditions - and I'm very encouraged by what I felt," he said.

"The car feels strong, very similar to last year's car, in fact. It doesn't take long to get used to the new buttons in the cockpit [KERS & front-wing flaps] but the real test for everyone now is to understand the slick tyres ahead of the first race in Melbourne next month."

Vettel completed just one lap less than the Briton as he continued with the development of the new Red Bull.

He finished ahead of Williams driver Kazuki Nakajima and Fernando Alonso in the Renault, the Spaniard the busiest man today with 133 laps.

"Today was all about getting mileage on the car, especially with the new KERS system," said Alonso.

"It was my first full dry day in the car and so I was able to learn a lot. We completed lots of laps, which is encouraging and now we will start working on the set-up of the car so that I can get more comfortable with it."

Today's times:

Pos  Driver        Team                       Time     Laps
 1.  Bourdais      Toro Rosso-Ferrari   (B)   1:18.493  128
 2.  Hamilton      McLaren-Mercedes     (B)   1:20.737   93
 3.  Vettel        Red Bull-Renault     (B)   1:20.738   92
 4.  Nakajima      Williams-Toyota      (B)   1:20.898   92
 5.  Alonso        Renault              (B)   1:21.307  133

All Timing Unofficial