Sepulveda surprised the leading group with an attack 4.5 kilometres out from the finish, before displaying strength and determination to keep chasers at bay on the steepest section of the ascent to the summit.
The Argentinian finished 15 seconds ahead of New Zealander Patrick Bevin (Israel Premier Tech), Harm Vanhoucke (Lotto Soudal), Australian Jay Vine (Alpecin-Fenix) and Nairo Quintana (Arkea-Samsic).
"Since the beginning of the year, the team told me I would be coming here and I was looking for a good result on this stage," Sepulveda said.
"I won and I don't believe it, but I'm very happy. I've put in a lot of years of work and it paid off."
Quintana had threatened to break away on several occasions during the climb but the Colombian could not gain the necessary separation due to the presence of Vanhoucke and Vine.
Anders Johannsen (Uno-X) and Dawit Yemane (Bike Aid) were the next to try and break away on the hors categorie climb but they, too, failed to gain ground.
It wasn't until Sepulveda's acceleration that an attack properly materialised; with an advantage rising as high as 20 seconds with three kilometres remaining and the road ramping up once again.
Bevin did most of the chasing in the closing kilometres and eventually outsprinted Vanhoucke, Vine and Quintana on his way to a second-placed performance that also moves him to the same spot in the general classification, 14 seconds behind Sepulveda.
The Drone Hopper-Androni star is within reach of an overall Tour of Turkey victory, though he remains coy on his chances after finishing on the podium in two previous iterations.
"I don't know, there are still four days to go," Sepulveda added.
"There were a lot of crashes yesterday, and I fell two times. I had a little pain, but I won today so I'm happy."
Australian Jay Vine moved into third overall on the standings, hoping that there would be an opportunity to fight for the top spot on the podium over the next few stages.
"There's no hiding the fact I wanted more," said Vine on social media. "Not sure how the GC will play out, with the other parcours, it's very hard picking up extra time to the leaders, but let's see how it goes."
Share
Watch the FIFA World Cup 2026™, Tour de France, Tour de France Femmes, Giro d’Italia, Vuelta a España, Dakar Rally, World Athletics / ISU Championships (and more) via SBS On Demand – your free live streaming and catch-up service. Read more about Sport


