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Brtitain's Mark Cavendish celebrates after winning the fifth stage.

Among the top contenders behind Cancellara, Cadel Evans of Australia holds third place, 39 seconds back, and last year's runner-up Andy Schleck of Luxembourg is sixth, 1:09 back. Contador is ninth, 1:40 back, and United States rider Armstrong is 2:30 back in 18th.

After crashing in Monday's Stage 2 and popping a tire and losing time in the third stage on Tuesday, Armstrong turned his attention to keeping out of trouble in frenzied finishes like Thursday's that play to sprinters' strengths - and looking ahead to the first mountain stage on Sunday.

"I don't know how selective the Alps will be," Armstrong said, referring to a possible shakeout among contenders on the climbs. "Those big group sprint finishes - I'm looking forward to get behind me."

"It was definitely a stressful first four or five days, unlike anything I think we've seen, and I think even people who have been at this event for 40 years would agree," he said.

"This is an extremely volatile, dangerous first week," Armstrong added. "It's just time to move on."

Riders embark on the longest stage of this year's Tour for Friday's Stage 6, a 227.5-kilometer jaunt from Montargis to Gueugnon. The forecast is for humidity and temperatures of up to 35 C (95 F).

The Tour ends July 25 in Paris.