Martinez broke away 13 km from the finish in Burgos

Spain's Inigo Landaluze was second and Ukrainian Volodymir Gustov third, while Alejandro Valverde finished in the main peloton to maintain his overall lead.

Martinez said: "People had me labelled as a rider who was always getting into breaks but who never succeeded in winning but today I proved them wrong." Reigning champ Denis Menchov withdrew from the race with stomach problems.

Menchov was awarded the 2005 Vuelta title after winner Roberto Heras tested positive for blood-boosting drug EPO.

Stage 11 results:

1. Egoi Martinez (Spain / Discovery Channel ) 4:20:32"
2. Inigo Landaluze (Spain / Euskaltel ) +55"
3. Vladimir Gustov (Ukraine / Team CSC )
4. Thor Hushovd (Norway / Credit Agricole ) +3:35"
5. Alexandre Usov (Belarus / AG2R )
6. David Loosli (Switzerland / Lampre )
7. Andrea Moletta (Italy / Gerolsteiner )
8. Theo Eltink (Netherlands / Rabobank )
9. Scott Davis (Australia / T-Mobile )
10. Joaquin Rodriguez (Spain / Caisse d'Epargne )

General classification:

1. Alejandro Valverde (Spain / Caisse d'Epargne ) 45:54:45"
2. Andrey Kashechkin (Kazakhstan / Astana ) +27"
3. Carlos Sastre (Spain / Team CSC ) +44"
4. Jose Angel Gomez Marchante (Spain / Saunier Duval ) +56"
5. Alexandre Vinokourov (Kazakhstan / Astana ) +1:38"
6. Janez Brajkovic (Slovenia / Discovery Channel ) +2:05"
7. Danilo Di Luca (Italy / Liquigas ) +2:21"
8. Manuel Beltran (Spain / Discovery Channel ) +2:28"
9. Vladimir Karpets (Russia / Caisse d'Epargne ) +3:02"
10. Sergio Paulinho (Portugal / Astana ) +3:42"