Milan - King of the mountains leader Julian Arredondo has won the 18th stage of the Giro d'Italia on Thursday as Colombian compatriot Nairo Quintana held onto the overall race lead.
Trek's Arredondo broke clear of an escape group in the final 4km and held off another compatriot, Fabio Duarte, to claim his maiden victory in the race.
"I've been trying since the start to win a stage," said Arredondo, who was quick to thank his team's for keeping faith.
"I want to thank the team for believing in me when I was a total unknown. I've been making huge sacrifices over the years without anyone really believing in me."
Irishman Philip Deignan of Team Sky took third on the stage, 37sec back at the end of the 171km stage from Belluno to the Panarotta Refuge.
Australian 2011 Tour de France winner Cadel Evans was the big loser as he was dropped by the group of favourites and lost his podium place.
The 37-year-old BMC rider dropped from third overall overnight to ninth.
Quintana, who took the leader's 'maglia rosa' (pink jersey) by winning Tuesday's 16th stage, leads another Colombian, Rigoberto Uran, by 1min 41sec with Frenchman Pierre Rolland up to third overall at 3min 29sec.
"I'm satisfied," said Quintana, who will be happy to have saved precious energy for two tough stages ahead, a crucial individual time trial to Monte Grappa on Friday and the mountain stage to Monte Zoncolan on Saturday's penultimate day.
"The stage was pretty easy. There were a few attacks going up the final climb, but we managed to control the riders who were a threat to us.
"I had good legs and I'm feeling better as the days go on. I'm optimistic of doing well in the Monte Grappe time trial."
Quintana, however, added: "The Giro isn't over yet."
Uran, runner-up last year to Italian Vincenzo Nibali, said: "The time trial to Monte Grappa will be crucial, for me and the Giro."
Arredondo had signalled his credentials earlier this season with two stage wins at the Tour of San Luis in Argentina and a fifth place overall at Tirreno-Adriatico, the latter prompting ambitions of a stage win at this year's Giro, where he is also hoping to secure the climber's jersey.
In a thrilling finale in which the lead changed hands several times, the Colombian achieved one of those objectives and boosted his chances in the second by soloing to the biggest win of his career.
After Belgian Thomas De Gendt and Italian Franco Pellizotti had both tried their luck, Arredondo finally made a solo break stick.
Duarte, who had covered an earlier dig from Arredondo 6km out, tried to respond but this time could not bridge the gap.
Arredondo added: "I got into the breakaway early on to try and score some points for the climber's jersey. On the final climb I wanted to attack, but my team kept telling me to relax, to wait a little.
"In the end it was good advice because it paid off."
Behind the breakaway riders, the battle was on for podium places as Movistar's Quintana expertly marshalled any danger to his overall lead.
Evans was the first to crack giving Rolland, whose attacks thinned out the favourites' group, the chance to snatch a podium spot.
"I'll keep on going as I have from the start," said Rolland. "Taking things day by day. Today I tried to snatch back some time in the final climb. I dug deep about four kilometres from the finish, but the chasers came back to us."
However, he has two riders just two seconds back after Italian Fabio Aru of Astana pulled back a handful of second on the Europcar rider.
Aru is fourth on the same time as fifth-placed Rafal Majka with Italian Domenico Pozzovivo just 23sec behind Roland in sixth.
Results from the 18th stage of the Giro d'Italia, a 171km ride from Belluno to Rifugio Panarotta:
1. Julian Arredondo (COL/TRE) 4hr 49min 51sec, 2. Fabio Duarte (COL/COL) at 17sec, 3. Philip Deignan (IRL/SKY) 37, 4. Franco Pellizotti (ITA/AND) 1:20, 5. Edoardo Zardini (ITA/BAR) 1:24, 6. Thomas De Gendt (BEL/OPQ) 1:38, 7. Ivan Basso (ITA/CAN) 1:43, 8. Dario Cataldo (ITA/SKY) 1:59, 9. Fabio Aru (ITA/AST) 2:43, 10. Nairo Quintana (COL/MOV) 2:46, 11. Rigoberto Uran (COL/OPQ) 2:46, 12. Domenico Pozzovivo (ITA/ALM) 2:49, 13. Pierre Rolland (FRA/EUC) 2:49, 14. Rafal Majka (POL/TIN) 2:49
21. Cadel Evans (AUS/BMC) 4:24
1. Nairo Quintana (COL/MOV) 77hr 58min 08, 2. Rigoberto Uran (COL/OPQ) at 1:41, 3. Pierre Rolland (FRA/EUC) 3:29, 4. Fabio Aru (ITA/AST) 3:31, 5. Rafal Majka (POL/TIN) 3:31, 6. Domenico Pozzovivo (ITA/ALM) 3:52, 7. Ryder Hesjedal (CAN/GRM) 4:32, 8. Wilco Kelderman (NED/BKN) 4:37, 9. Cadel Evans (AUS/BMC) 4:59, 10. Robert Kiserlovski (CRO/TRE) 8:33
13. Ivan Basso (ITA/CAN) 21:25
18. Damiano Cunego (ITA/LAM) 39:18
20. Michael Rogers (AUS/TIN) 41:38