Colombian was first across each of today's three climbs. Meanwhile Cadel Evans slips to 9th with Pierre Rolland going 3rd...

Julian Arredondo of Trek Factory Racing has won Stage 18 of the Giro d'Italia, winning from the break after attacking on the climb to the Category 1 summit finish at Rifugio Panarotta, and all but sealing his win in the mountains competition.

In a race in which Colombian riders have come to the fore, his compatriot Fabio Duarte of Team Colombia was second, around 17seconds behind with Sky's Philip Deignan third, a further 20 seconds down.

Movistar's Nairo Quintana retains the overall lead, but with attacks taking place in the GC group on the final climb, there will be some reshuffling of the order of the rest of the top ten, with the man with most to celebrate being Europcar's Pierre Rolland, who moves to third overall.

That position is far from secure, however - Astana's Fabio Aru and Rafal Majka of Tinkof-Saxo both lie just 2 seconds behind him, and there could well be more changes following tomorrow's mountain time trial to Montegrappa.

Besides being first across the summit finish, Arredondo also took maximum points on the first two climbs, the Passo San Pellegrino and the Passo del Redebus, with Sky’s Dario Cataldo his closest challenger on both occasions, meaning the Sky man moves to second in the competition.

For the second day running, Thomas De Gendt of Omega Pharma-Quick Step attacked off the front of the break in the latter part of the stage.

On the third and final climb of the 171km stage from Belluno, the Belgian found himself around 15 seconds clear of his breakaway companions as he headed under the 10km to go banner, with the overall contenders’ group around 5 minutes down.

Three other members of the escape group set off in pursuit of De Gendt, the Sky pair of Cataldo and Deignan, plus  Arredondo.

Subsequently, they were joined by Duarte and Franco Pellizotti of Androni Giocattoli, the group finally reeling in De Gendt.

The 14-man group they had belonged to got away on the first climb of the day and besides De Gendt and Pellizotti contained two other Giro stage winners –Matteo Rabottini of Neri Sottoli, and Cannondale’s Ivan Basso, a two-time overall Giro champion.

With around 6km remaining, Arredondo attacked, Duarte going with them and the pair were joined Deignan, with De Gendt and Pellizotti also getting back on.

Coming into the final 5km, De Gendt attacked again, this time Pellizotti going with him and quickly getting clear in what is his home region, only to be caught by Duarte then Arredondo, who was next to attack and get out front in his own in what would prove to be the stage-winning move.

Meanwhile, behind, the first attacks were being launched from the GC group, instigated by the Europcar pair of Romain Sicard and Rolland, with BMC Racing’s Cadel Evans among those put in trouble, losing well over a minute to his rivals.

With around 3km to go, Rolland attacked again, and this time got daylight over his pursuers as well as the time on Evans that puts the Frenchman into a podium position.

Following his victory today, Arredondo said: “My main goal was a stage win in the Giro d’Italia. I tried in breakaways in the first week: in one of them, I was caught 2 km from the finish. Today, I had the Maglia Azzurra  so I joined the breakaway. I went over the first two categorised climbs in first place, and I didn’t imagine for a moment that today  could be my day. my coach, Josu Larrazabal, believed in me.

"At the foot of the final climb, I wanted to attack, but my [sports director] Josu said, 'Take it easy, not yet.'  Then, much higher up, he said, 'Julián, now!' So I won the stage because of his advice. He gave me the calm and the patience, and the day ended perfectly for me. I dedicate this stage win to him.

He revealed however that he had nearly abandoned the race earlier this week: “I have had difficult times during this Giro. I have even thought of abandoning. Two days ago, on the Stelvio, I thought I’d finish last. Josu put me in the car, warmed me up, and gave me the courage to restart.”

He went on: "I’ve been through difficult periods in my career. I was 6th in the UI23 standings in Italy, but no one wanted to sign me. I called Team Colombia, who said they’d call me back, but never did.

"Then Andrea Tonti called me and said,  'Trust me, come and ride for my team.' Little by little, the path has led me to moments of glory., After years of struggle and hard work, I’m finally with a team that provides me calm and security. I’ve shown that I can perform and I have put my trust in the right people.”

Race leader Quintana, meanwhile, isn't counting his chickens. ”Until the finish line in Trieste, nothing is certain," he said. "What I know is that my physical sensations are better every day. I like the route. There is a big altitude gain, and I think it suits me. I hope to ride well. I’m healthy now, and the main thing is to lose no time and keep the Maglia Rosa.

Looking ahead to tomorrow's time trial, he said: “Of Urán and myself, I don’t know who will do better because there’s some flat too. Uran could ride at  a high level tomorrow, and there are other riders who can do well, including Pozzovivio, Rigoberto, and Pierre Rolland, who looks strong.”

Speaking about his friendship with Uran, he added: “We have a very good relationship. We enjoyed living together in Pamplona. We got on very well. I like his way of being. However, it doesn’t affect my way of racing because it’s my job, I have my team. I’m the leader when the team chooses. My friendship with Rigoberto was born outside cycling. In the races we have to ride as rivals.”

Born in Scotland, Simon moved to London aged seven and now lives in the Oxfordshire Cotswolds with his miniature schnauzer, Elodie. He fell in love with cycling one Saturday morning in 1994 while living in Italy when Milan-San Remo went past his front door. A daily cycle commuter in London back before riding to work started to boom, he's been news editor at road.cc since 2009. Handily for work, he speaks French and Italian. He doesn't get to ride his Colnago as often as he'd like, and freely admits he's much more adept at cooking than fettling with bikes.