Boonen won the 124-mile trek from the Burgundy town of Semur-en-Auxois toward the foot of the Alps in Bourg-en-Bresse. Friday's was the last stage before three days in the Alps.

Boonen, a former world champion, collected his fifth Tour stage victory and his first since 2005 by outpacing Spain's Oscar Freire and German Erik Zabel in the final dash.

"I'm really happy," said Boonen. "The legs have been strong from the first day, but this year things haven't happened so well. I haven't had a lot of luck."

Cancellara finished in the trailing pack, and holds a 33-second lead over Germany's Andreas Kloeden in second. Filippo Pozzato of Italy is third, 35 seconds behind.

Kloeden and his Astana teammate Alexandre Vinokourov, both seen as potential title contenders, cruised in the back of the pack nursing painful injuries sustained in crashes during Thursday's ride through hilly terrain.

Britain's Bradley Wiggins took the spotlight for most of the stage, breaking away after 1.2 miles and building a lead of more than 17 minutes before the pack caught him during the last 4.2 miles.