The Tour de France star pedaled up out of his saddle in a mountain stage, dusted his rivals and seized the yellow jersey that he knows all too well and covets so much.

This time, it wasn’t Lance Armstrong, but his teammate and one-time rival Alberto Contador, who won Sunday’s 15th stage and made a case to be the Texan’s successor at cycling’s premier event.

After such a dominant display in which Armstrong finished in ninth place — 1 minute, 35 seconds after Contador and among other also-rans — he sees his chances of an eighth Tour victory fading.

“It will be hard. A day like this really shows who’s the best, and I wasn’t on par with what is required to win the Tour,” Armstrong said. “That’s the reality; that’s not devastating news or anything.”

He added, “I gave it everything that I had, and I wasn’t the best.”

As the three-week race entered the Alps, the 26-year-old Spaniard recovered the celebrated shirt that he hadn’t worn since his Tour victory in 2007.

He made it clear he’ll be the man to beat this year.

Race contenders knew that after a week of mainly flat stages that didn’t alter the top standings much, the 128.9-mile ride from Pontarlier, France, to the Swiss ski resort of Verbier was critical.

Armstrong rose from fourth to second in the standings but lost time to Contador, whom he now trails by 1 minute, 37 seconds.

Now, he sees his job as serving as a “domestique” — or support rider — for Contador.

Ten breakaway riders had set the pace from early on in the stage and chiseled out a maximum gap of 4:40 by the 78-mile mark, before the peloton gradually started closing in.

Rivals of the Astana teammates — notably the Danish team Saxo Bank — pressed the pace or tried to attack as the final climb loomed, but Contador held off every assault, then launched his own.

About one-third of the way up the 5.5-mile ascent to Verbier, Contador burst ahead of other pre-race favorites and kept extending his lead all the way to the finish.

“Saxo didn’t play around. They hit the bottom full-gas, we saw that coming, so we were perfectly on the wheel,” Armstrong said. “I think the thing to note is that Alberto responded.”

Riders get a rest day today before the two other Alpine stages, an individual time trial in Annecy on Thursday and a ride up the dreaded Mont Ventoux on Saturday.

The Tour ends Sunday on the Champs-Elysees in Paris.

“Hey, (if) we ride into Paris with the yellow jersey on the team, I’m cool with that,” Armstrong said. “I got seven of ’em at home.”