Lance Armstrong had only one goal today as temperatures soared in the Tour de France--damage limitation.

With tough climbs in the Pyrenees ahead of them next week, the overall leaders sat back for the third consecutive day. Italian Salvatore Commesso charged to victory in today's 13th--and longest--stage.

Armstrong retained his lead of 7 minutes 44 seconds. Spaniard Abraham Olano, who came in 36th in the stage, is in second place overall. Armstrong said earlier today that he was happy letting other cyclists battle it out between themselves--as long as they weren't his top rivals.

As temperatures hit 102 degrees, the conditions were clearly not ideal for the 27-year-old American, who says he prefers riding in the cold despite his Texas origins.

The same could not be said for Commesso, who broke off with more than a dozen other riders just a few miles into the stage.

"At first I thought to myself, 'There's so long to go. You're crazy, you'll never last all the way. It's impossible,' " a smiling Commesso said after the race. "But in the end I was helped by the fact that the main contenders weren't up with us."

Commesso narrowly edged fellow Italian Marco Serpellini in a final sprint after a head-to-head battle that lasted more than 15 miles. Italian Mariano Piccoli finished third.

It was the sixth stage on this year's Tour won by an Italian.

"Now, my next objective is to get to Paris and finish the Tour," Commesso said.

Today's stage was a 147-mile ride between Saint-Flour and Albi, a fast descent from the high plateaus of the Auvergne region to the heart of the French Midi, about 558 feet above sea level.

Albi, which has a renowned Gothic cathedral dating from the 13th century, is the birthplace of painter Henri Toulouse-Lautrec.

The Tour passed sunflower fields and red-tiled villages where locals skipped the siesta to sit roadside, waving flags and applauding the riders from any patch of shade they could find.

Surprisingly, none of the top-placed riders needing to claw back some of Armstrong's lead has attacked him as the race criss-crosses the French countryside.

Instead, Armstrong, who has staged a remarkable recovery from cancer that had spread to his brain and lungs, has been leading the main pack alongside his U.S. Postal Service teammates, keeping a close eye on trailing rivals while lesser names win stages.

Armstrong is the first American racing for an American team to have a realistic chance of winning the Tour. When American cycling legend Greg LeMond won in 1986, 1989 and 1990, he raced for European teams.

Sunday's stage is between nearby Castres and Saint Gaudens at the foot of the Pyrenees. Monday is a rest day.

The Tour ends on the Champs-Elysees in Paris on July 25.