Former World No.1 Laurent Jalabert became the new overall leader at the Tour de France after his ONCE team convincingly won Tuesday's time trial.

The 31-year-old Frenchman's team finished the 43-mile (70km) race from Nantes to the Atlantic port of Saint-Nazaire in 1 hour, 25 minutes and 36 seconds.

But the team were then shocked by a 20 second penalty for failing to respect the proper distance between them and the team car.

Defending champion Lance Armstrong and his U.S. Postal team were second, 26 seconds behind on revised time. Jan Ullrich's Deutsche Telekom came third, 1 minute, six seconds behind.

Britain's David Millar, of the Cofidis team, had held the yellow jersey since Saturday's opening individual time trial, but he slipped well back down the field as Cofidis finished two minutes 33 seconds behind ONCE.

We were meticulous down to the last detail

Laurent Jalabert, ONCE

It was the first time since 1998 that a Frenchman had won the yellow jersey.

"This stage was very important to us," Jalabert said. "We were meticulous down to the last detail."

The teams set out from the city of Nantes with a strong, energy-sapping headwind buffeting them all the way.

Racing against the clock, teamwork and communication was vital. Riders shuttled back and forth every few hundred metres to take turns against strong winds.

Headwind

Most of the race was flat except for a steady climb over a long bridge heading toward the finish.

Scot David Millar wears his yellow jersey for the last time in the team time trial

"There was a block headwind all the way," said Credit Agricole's Stuart O'Grady. "Coming over the bridge was just hell."

Armstrong excelled in last year's time trials as he headed toward an incredible victory in cycling's toughest event, just three years after being diagnosed with cancer.

In the run-up to this year's race, his team again has spent hours trying to perfect its technique in the time trial and was looking for a good dividend on Tuesday.

The 20-second penalty on ONCE moved Armstrong up from fourth to third, only 24 seconds adrift of Jalabert.

Favourites

The result saw Millar slip to 24th place as Jalabert became the first French cyclist to head the race since Laurent Desbiens in 1998.

Such is the dominance of ONCE after the fourth stage, they now occupy seven of the top 10 positions in the overall standings, with Spaniards David Canada and Abraham Olano second and fourth, 12 and 35 seconds behind respectively.

Jalabert, who last wore the yellow jersey in 1995, addedd: "Mary Pierce won at Roland Garros, we've just won Euro 2000, and now this - it shows the French are winners.

The last team of Bonjour dropped six minutes and 25 seconds in total.