BAGNERES-DE-LUCHON, France – The gloves have come off at the Tour de France.

Andy Schleck was fighting mad after dropping his chain during a tough climb Monday and then losing the overall lead when defending champion Alberto Contador unabashedly sped ahead to take the yellow jersey.

“He can be nervous for the next days … this gives me anger,” said Schleck, vowing revenge. “I’m not the one who will get chased any more, I’m the one who chases. That’s a big difference.”

The episode highlighted the often-unclear etiquette of cycling’s greatest race, where the wearer of the yellow jersey is conferred almost queen-bee-like respect – and taking advantage of mishaps out of his control is frowned upon.

The breach came on a day when France’s Thomas Voeckler came out of a long breakaway to win the 15th stage from Pamiers to Bagneres to Luchon, finishing a 116.5-mile trek that included the merciless Port de Bales climb in 4 hours, 44 minutes, 51 seconds.

Contador, who gained time while Schleck was putting his chain back on and during a high-speed downhill to the finish, crossed 2:50 back in seventh, while Schleck came in 12th – 3:29 after Voeckler.

After more than two weeks and 1,800 miles of racing, the two-time champion from Spain leads Schleck by merely 8 seconds. Spain’s Samuel Sanchez is third, 2:00 back.

Schleck hit the accelerator in an attack about 2.5 miles from the top of the Port de Bales, but his chain came unfurled. For a few seconds he pedaled on in disbelief before stopping to fumble with his chain as Contador and other top riders sped by.

At the finish, Schleck swatted back reporters and gritted his teeth in anger. Contador said such woes are part of the sport, and insisted he didn’t know about his rival’s troubles right away.

“Those are the circumstances of the race,” he said. “I knew there would be a debate after that, but I attacked before I knew he had a problem with his chain, and I was already ahead when I knew it. I understand he’s disappointed.”

Lance Armstrong said Monday’s case wasn’t clear cut.

“It’s better to wait, but this is different because this was the last climb of the race, and the race was really on,” said Armstrong, who is 31st overall, 40:31 behind Contador.

Schleck vowed Monday’s episode would become a big motivator.

“I’ve got fire in my belly,” he said. “The race is not finished, and I will take my revenge in the next days.”