Julien Arrendondo of Trek Factory Racing took victory on stage eighteen of the 97th Giro D'Italia.
With Nairo Quintana still pretty in pink, another stage of four climbs including a mountain top finish rolled out from Belluno heading for Rif. Panarotta at the end of a 171km stage.
It was not until twenty seven kilometres in and on the San Pellegrino climb that the first attacks started to occur. Jualian Arredondo (Trek Factory Racing), Dario Cataldo (Team Sky), Edoardo Zardini (Bardiani CSF), Emanuele Sella and Franco Pelitzotti (Both Androni) formed the break which was added to by Phillip Deignan who was behind Arredondo as he crested the San Pellegrino climb to take maximum points and extend his lead in the King Of The Mountains competition.
Arrendondo and Deignan were caught with sixty seven kilometres gone and joined a fourteen man group in Pellizotti, Sella, Keizer, Zardini, Basso, Duarte, Wellens, De Gendt, Rabottini, Losada, Cataldo, Deignan, Rovny and Arredondo which was 5.54 ahead of the peloton and then 7.14 ahead with just over 81kms to go.
Tim Wellens of Lotto took the sprint at Wellesse ahead of Emmanuele Sella before the break started on the Passo del Redebus climb with a lead of 5.37.
Julien Arredondo led out Dario Cataldo of Team Sky on the closing stages of the category two climb and sprinted to ensure that he took the maximum fourteen points.
The leaders were still 7.22 clear going into the final twenty kilometres on what was now a showery afternoon.
Thomas De Gendt of Omega Pharma Quick Step attacked on the foot of the Rif. Panarotta climb which has an average gradient of 7.9% with 14% maximum ramps, after passing through Levico Terme.
Belkin's Martin Keizer set off after De Gendt as Europcar worked on the front of the maglia rosa group who were 5.20 with thirteen kilometres left.
With ten kilometres to go, Cataldo left the chasing group and stormed after De Gendt, who was on a 14% section of the climb. Deignan and Arredondo joined Cataldo and the trio went past De Gendt followed by Duarte with 6.2kms left.
Arredondo took to the front once whilst behind him, Pierre Rolland was putting some distance between himself and Cadel Evans.
Fabio Duarte was twenty seconds behind Arrendondo who kept going and won in 4.49.51 to take the biggest win of his career. Duarte finished second seventeen seconds down with Team Sky's Philip Deignan third, 37 seconds down followed by Pellizotti and Zardini.
Naira Quintana finished tenth 2.46 down but keeps his leaders jersey with a 1.41 lead of Rigobert Uran. Cadel Evans has dropped to ninth.