ARENBERG, France -- Just four days into the Tour de France, Lance Armstrong is off to a rough start.
On the cobblestones in Tuesday's third stage, on which he had been expected to excel, the seven-time champ instead popped a tire, lost time changing it and fell back of his main rivals.
The 132-mile ride from Wanze, Belgium, to Arenberg Porte du Hainaut in France was the most dreaded stage of Week 1 -- with seven sections of bone-jarring cobblestones that threatened injury, bike damage or lost time for title contenders.
Thor Hushovd of Norway, leading a six-man group, won the stage in a final sprint. Fabian Cancellara, the Swiss rider who won the prologue, was right behind -- and recovered the leader's yellow jersey he had ceded Monday to Frenchman Sylvain Chavanel.
For Armstrong, the bigger threats are riders such as defending champion Alberto Contador of Spain, 2009 runner-up Andy Schleck of Luxembourg and two-time runner-up Cadel Evans of Australia. They all leapfrogged the 38-year-old Texan. They will be tough to overcome when the next big challenges await in the Alps in Week 2 and a punishing four-day run in the Pyrenees in Week 3.
"Our chances took a knock today," Armstrong said. "I'm not going home, we'll stay in the race and keep trying."
Astana team leader Contador avoided disaster and rode the last 18 miles with the brake jammed against his rear wheel.
"I knew that if I changed the bike would be much worse and I preferred to continue with the wheel braking," he said. "I couldn't stand up, but hey, we saved the day."
Schleck was fifth in the stage, clocking the same time as Hushovd: 4 hours, 49 minutes, 38 seconds. In the splintered pack, Contador was 13th, 1 minute, 13 seconds back. Armstrong placed 32nd -- 2:08 behind.
Overall, Cancellara leads Geraint Thomas by 23 seconds, and two-time Tour runner-up Evans is third: 39 seconds back. Contador is ninth, 1:40 back,; Schleck is sixth, 1:19 back; and Armstrong sank to 18th, 2:30 back, after entering the day in fifth overall.
The cobblestones stage, the first at the Tour since 2004, followed two straight stages marred by crashes on slick roads that caught up Contador, Schleck and Armstrong.
Organizers took a gamble by running the riders over the treacherous, roughhewn stones, hoping to inject drama to the race. The move appeared to be vindicated.
"I'm not sure I'm a fan of the cobblestones in the Tour de France," said Bjarne Riis, the Saxo Bank team manager, "but it was a spectacular race."
Armstrong, who has dealt with cancer, will have to prove that, at 38, he's still got some fight in him if he wants to win.
Armstrong began the stage ahead of his general classification rivals. Now, he trails them: Contador is 50 seconds ahead, Evans is nearly two minutes ahead. Britain's Bradley Wiggins has 41 seconds on Armstrong.
They're likely to pounce if Armstrong tries to get in the front now. It's a far cry from his heyday, when he methodically worked to ensure his rivals were eating his dust from the outset.
"Bad luck," Armstrong said of his mishap.
Some had worse luck: Andy Schleck's brother Frank, in the middle of the Sars-et-Rosieres patch -- the fourth run of cobbles -- hurtled off his bike and onto the side of the road and did not get up, crouching in pain on the ground. He was taken to a hospital where he was diagnosed with a broken left collarbone.
After that spill, the pack splintered. Armstrong had a small lead over Contador after the fifth section, but then he punctured his tire in the sixth and the Spaniard's group rumbled by him until the Texan got a replacement.
"It's very frustrating," he said. "I'm not going to make any excuses. I was in good position ... there was the crash that split the group, we hung tough and tried to come back and just got a flat tire at the wrong moment.
"A 45-second wheel change, and they're gone, he added. "It was very difficult to come back."
Armstrong had predicted "carnage" during the stage, and many riders anticipated that some ambitions of victory could be all but lost.
Among the contenders, Armstrong lost out most on the day. The big winners were Evans, who jumped to the front of race contenders who are expected to far well in the mountains, and Contador -- whose abilities on the cobblestones were uncertain.
Armstrong had no hard feelings that the pack didn't wait for him like it had on Monday, when he and several other top contenders crashed -- prompting the Cancellara-led bunch to slow down.
"It's pro bike racing, it's dog eat dog," Armstrong said. "One day you're the peacemaker and the rational mind, and the next day you're taking advantage of every opportunity."
Cancellara, a teammate of the Schlecks who won the opening-day prologue, expressed "mixed feeling" about the day but was delighted to retrieve the leader's jersey.
"Yesterday I gave it up, today I took it," he said. "We can call it a good day for Saxo Bank despite the loss of Frank, a great friend."
Seven riders broke away early. Getting out front in such a stage doesn't just improve chances for a stage victory, it also can help avoid crashes -- which are more likely in the frenzied pack.
Armstrong's RadioShack team led the pack over the first bumps, with crowds getting up close but respecting a safe enough distance for the riders to get through.
At the second patch, dust flew as some riders sought to evade the cobblestones by riding on the dry dirt on the side -- but again, no riders went down. This time, the crowds kept back.
Chavanel wore the yellow jersey for Tuesday's ride into his home country, but he had to cope with two flat tires, along with a mechanical problem, and lost time on Cancellara.
The pack could get a more restful day on Wednesday, with a mostly flat 95-mile course from Cambrai to Reims, the capital of Champagne country.
Despite his setback Tuesday, Armstrong noted there's still a lot of racing left in the three-week race, which heads toward the Alps and later the Pyrenees before the Paris finish on July 25.
"It's the nature of the sport," he said. "Sometimes you're the hammer, sometimes you're the nail. Today I was the nail. I have 20 days now to be the hammer."