VITTEL, France — Lance Armstrong is ready to climb again, ready to leave the pack at the Tour de France after days of flat riding that belonged to sprinters.
After three days of sitting back in the main pack while others challenged for stage wins, the worst thing to happen to Armstrong was a small puncture to his back tire on Thursday's 12th stage. Nicki Sorensen of Denmark won it, Rinaldo Nocentini of Italy kept the yellow jersey, and Armstrong's tire was repaired within a flash.
Finally, it's back to serious business today as Armstrong goes up against his Astana teammate Alberto Contador on a tricky trek that features one grueling mountain climb.
"Tomorrow is hard, that is a real stage," Armstrong said Thursday. "The climb up Col du Platzerwasel is difficult, it is a long way. It is a longer day, and anything can happen."
Armstrong, who retired after his seventh straight Tour win in 2005 only to stun the cycling world by announcing he would race again this year, expects some of the contenders to make their move today.
"You have to watch all the rivals, even someone like [Denis] Menchov," Armstrong said of the Giro d'Italia winner. "Some might say he is five or six minutes behind and his race is finished, but if he gains back time, he has the Alps, and then if he is close enough on the [Mont] Ventoux, he could present a problem."
Armstrong briefly looked to be in trouble after about 37 miles Thursday, when he had to pull over to let his Astana team repair a puncture in his back wheel.
But after a few moments, four of Armstrong's teammates helped him catch up with the main pack again.
"Up and down all day long and was aggressive from the start," Armstrong said on his Twitter feed.
Although Nocentini will keep the yellow jersey heading into today's 13th stage, he is not considered a threat for overall victory -- and seemed to be saying he's done the best he can.
"It's a tough stage tomorrow, but I'm already really happy," Nocentini said.
He leads Contador by only six seconds and Armstrong by eight.
On Thursday, Sorensen earned the first stage win of his Tour career by breaking away and finishing well ahead of Laurent Lefevre.
Sorensen was part of a small group of seven riders who finished several minutes ahead of the main pack after foraging ahead unchallenged during the 131.4-mile trek from Tonnerre to Vittel, which featured six small hills.
The Danish veteran, after years as a support rider in Bjarne Riis' team, finished 48 seconds ahead of Lefevre.
"I'm 34 years old now, and it's a big thing for me to perform at this level at this age," Sorensen said. "I started bike racing when I was 19, and I always hoped that I could maybe go on for many years."
The chasing pack, including Nocentini, Armstrong and Contador, finished nearly six minutes behind him.
Astana rider Levi Leipheimer fell off his bike about 1.86 miles from the line in a crash involving two-time Tour runner-up Evans. Leipheimer had cuts and bruises on his right wrist, shoulder and back. He hopes to resume today.
"My wrist hurts, but surprisingly it's OK. It could have been a lot worse," Leipheimer said. "I was a bit surprised by a left corner ... my tire was sliding, and I couldn't quite save my bike from sliding out."
Associated Press Sports Writer Samuel Petrequin contributed to this report.