Climbing specialist Mayo mastered the tough Alpine course to win

The Spaniard, who won the race in 2004, shook off compatriot Alejandro Valverde 4km from the finish to cover the 169km in five hours 01.42 minutes.

Frenchman Christophe Moreau's third place moved him second in the overall table behind American Levi Leipheimer.

Denis Menchov dropped from second to sixth in the standings after a crash.

The Russian was able to get back on his bike but struggled on the last climb and crossed the line in 18th place.

It was also a miserable day for Friday's stage winner Ludovic Turpin, who has a suspected broken right hip after crashing on the descent of the infamous Col du Mollard.

Mayo's victory ended a two-year drought and the Spaniard said afterwards that he had believed a return to winning ways was imminent on the previous stage.

"The first sign in two years that I was back on track came on Friday's stage when I finished second," said Mayo, whose last win was overall in the Dauphine Libere in 2004.

"After that, my confidence really grew, and today I knew I could do something big.

"I was worried about Valverde in a sprint finish because he's fast, so I had to drop him. Fortunately for me, he cracked when I attacked four kilometres from the line."

Stage six results:

1. Iban Mayo (Spain / Euskaltel) 5:01:42"
2. Alejandro Valverde (Spain / Caisse d'Epargne) +1:21"
3. Christophe Moreau (France / AG2R) +1:37"
4. Levi Leipheimer (U.S. / Gerolsteiner) same time
5. Leonardo Piepoli (Italy / Saunier Duval) same time
6. Bernhard Kohl (Austria / T-Mobile) +2:00"
7. Jose Azevedo (Portugal / Discovery Channel) +2:37"
8. Francisco Mancebo (Spain / AG2R) +3:17"
9. Oscar Sevilla (Spain / T-Mobile) +3:26"
10. Pietro Caucchioli (Italy / Credit Agricole
same time

General classification: