GUEUGNON, France -- Lance Armstrong has his mind on the mountains.
The seven-time Tour de France champion is in 18th place after Friday's stage, which was won by Mark Cavendish for his second straight sprint-finish victory. If Armstrong is going to make a move, it may come in the climbs.
The weather was hot -- 95-degree heat -- and some tempers even hotter for the 141-mile sixth stage from Montargis to Gueugnon. Two riders broke out into a bike wheel-whacking brawl after the finish line.
"Guys were suffering the whole stage," Armstrong said.
Cavendish called the stage -- the longest this year -- his hardest ride so far.
"For us, these days are days when you can't necessarily win the Tour, but you can certainly lose it," Armstrong said, warning as he often does of the dangers of flat stages that end in frenzied sprints.
The top of the standings didn't change much. Barring crashes or mishaps, they rarely change a lot on flat stages. But with the Tour about to leave the lowlands, the climbers could take step up while the contenders test their rivals for weakness.
Saturday's seventh stage is a 103-mile route along six low- to mid-grade climbs in the Jura range from Tournus to Station des Rousses. But the first real shakeout of climbers' legs looms in Sunday's stage, featuring two tough climbs including an uphill finish into the Morzine-Avoriaz ski station.
"I would look for more animation and more attacks on Sunday," Armstrong said.
But will he attack?
"Probably not. I still would wait and watch the other guys," he said, anticipating that he'll need to conserve energy for four rides in the Pyrenees in Week 3 that are likely to have more impact on who wins.
Armstrong's last competitive test in mountains came in the Tour of Switzerland last month, where he finished an impressive second. He said he's in even better shape now.
"It was promising," he said, referring to the Swiss race. "But, to be honest, I feel a lot better now then I did then: On the bike I feel stronger, recovery feels better, I'm a little bit lighter, which I think makes a big difference. We'll see. It's all hype until you get out there and do it."
The man who beat Armstrong in Switzerland, Frank Schleck of Luxembourg, broke his collarbone Tuesday during a stage run over cobblestones. Armstrong lost time that day after blowing a tire and hurting his chances for an eighth Tour victory.
Defending champion Alberto Contador, the big favorite entering the Tour and one of the world's best climbers, is encouraged.
"Today I woke up with much better legs and that's important because tomorrow the difficulty starts, and I need to be at 100 percent," the Spaniard said.
Armstrong says his team is looking strong, with U.S. veterans Chris Horner and Levi Leipheimer, Germany's Andreas Kloeden and young Slovene star Janes Brajkovic all ready for the mountains.
"They'll be good," Armstrong said. "I think we can still have five guys there. ... Numbers will help us."
On Friday, Cavendish, of the U.S. team HTC Columbia, won a Tour stage for the 12th time in his career. He finished in 5 hours, 37 minutes, 42 seconds and was followed by Tyler Farrar of the U.S. and Alessandro Petacchi of Italy.
The likely Tour title contenders crossed three seconds after Cavendish. Contador was 28th, Armstrong was 38th and overall race leader Fabian Cancellara 41st.
Cancellara retained the yellow jersey and two-time Tour runner-up Cadel Evans of Australia held third place, 39 seconds back. Last year's runner-up, Andy Schleck of Luxembourg, is sixth, 1:09 back. Contador is ninth, 1:40 behind, and Armstrong is 2:30 back in 18th.
The heat appeared to take a toll on Carlos Barredo of Spain and Rui Costa of Portugal. They fought after the finish, although the reason was not immediately clear. Internet video showed Barredo of the Quick Step team charging Costa and attempting to hit him over the head with a bike wheel.
Costa, who rides for Caisse d'Epargne, tried punching Barredo in the face several times before both fell to the ground screaming at each another. They were separated and Tour organizers cited both for "insults and threats" and "incorrect behavior," fining each about $190. It was not immediately known if there would be further discipline.
Cavendish's victory came a day after he broke down in tears following his win the fifth stage.
"I'm really happy," he said. "I'm speaking better today because I was pretty emotional yesterday."
Farrar's sprint attempt suggested the Garmin-Transitions rider's condition has improved since he broke his left wrist in one of numerous crashes on rain-slicked roads in Monday's second stage.
"I'm still not 100 percent," Farrar said in French on French TV. "Maybe I'm stupid not to stop after the break, but today I was feeling better."