CASTELSARRASIN, France — Italy’s Daniele Bennati won the 17th stage of the Tour de France and Spain’s Alberto Contador became the new overall leader yesterday, a day after Michael Rasmussen was sent home for lying to his team in another devastating jolt to cycling’s premier event.

Bennati won a sprint at the end of the 117-mile ride from Pau to Castelsarrasin, as the doping-marred Tour staggered north toward its finish yesterday in Paris. Bennati, riding for the Lampre Fondital team, won a Tour stage for the first time. He led a small breakaway group and finished in 4 hours, 14 minutes, 4 seconds. Markus Fothen of Germany was second and Martin Elmiger of Switzerland was third.

Contador had been second overall to Rasmussen after Wednesday’s last ride in the Pyrenees, when the Dane’s Rabobank team took him out of the race.

“I would have liked to take it on Wednesday,” said Contador, who finished second to Rasmussen in that stage, up the Col d’Aubisque. “But these are particular circumstances, and that’s just the way it is.”

The last time there was no yellow jersey was when leader Rolf Sorensen crashed and was too injured to continue in 1991, according to the Tour’s Web site.

Contador, a 24-year-old Discovery Channel rider, leads by 1 minute, 53 seconds over Cadel Evans of Australia. His Discovery teammate, Levi Leipheimer of the United States, is third, 2:49 back. Rasmussen was ousted by his team for lying about his whereabouts during pre-race training, the third blow this week to the venerable 104-year-old Tour. In recent days, two riders — including star Alexandre Vinokourov — were thrown out because of positive drug tests.

French President Nicolas Sarkozy said during a trip to Dakar, Senegal, that he supports Tour organizers “because they have the courage to eject cheaters.”

“Let’s stop the hypocrisy — it’s been around for decades,” Sarkozy said.

Some French newspapers yesterday declared the Tour dead and said it should be stopped after the startling announcement Wednesday night that Rasmussen’s team was sending the Dane home.

Team spokesman Jacob Bergsma said Rasmussen’s withdrawal was ordered by sponsor Rabobank. It was linked to “incorrect” information that Rasmussen gave to the team’s sports director over his whereabouts last month. Rasmussen missed random drug tests May 8 and June 28, saying he was in Mexico. But a former rider, Davide Cassani, said he had seen Rasmussen in Italy in mid-June.