Miguel Lopez of Astana took victory on the sixth stage of the Tour De San Luis in Argentina.
A 159.5km Queens Stage from La Toma to Merlo featured the sixteen kilometre long El filo de los Comechingones climb which had gradients up to 15%.
Three riders in Eduard Grosu (Nippo Vini Fantini), Matej Mohoric (Lampre) Juan P. Magallanes (México) formed a break and they were 5.30 ahead of the peloton which contained race leader Eduardo Depulveda of Fortuneo Vital Concept with 84kms to go.
They were able to extend that to 7.30 and 7.45 with sixty kilometres left to race.
The gap did descrease but with twenty five kilometres remaining, it stood at 4.20 but as they started on the final climb, the gap was down to 55 seconds with ten kilometres to go.
Only Grosu could stay with Lucero, Carapaz and César Rojas who could the escapers.
Astana and Movistar set the pace and everyone was back together with seven kilometres left.
Rodolfo Torres, who was only 1.37 down on GC and Josue Gonzalez attacked but Gonzalez was soon dropped and Nairo Quintana, Miquel Lopez, Dayer Quintana, Torres and the race leader Sepulveda took over until the Quintana's and Lopez broke away.
Lopez made his move and he rode to victory in a time of 4.39.49, ahead of Nairo Quintana and Dayer Quintana.
Eduardo Sepulveda came in fifth but twenty three seconds down and that was enough for Dayer Quintana to take the lead going into the final stage with a margin of twenty seconds and 35 over Nairo Quintana.