Alberto Contador of Astana won the sixth and penultimate stage of the Dauphine Criterium on Saturday as RadioShack's Janez Brajkovic tightened his grip on the race lead. Slovenian Brajkovic started the day with a lead of 1:41 on two-time Tour de France champion Contador and maintained his advantage after repelling a series of attacks by the Spaniard on the 13.8km climb to Alpe d'Huez.