Giovanni Visconti claimed his first-ever stage win on the Giro d'Italia after digging deep to conquer the gruelling conditions that continue to blight this year's race.

The Movistar rider was part of an initial six-man breakaway group that pulled clear of the peloton with 82 kilometres remaining of the 145km stage out of Cesana Torines.

Visconti asserted his dominance as snow arrived to add more danger to an already-gruelling Alpine trek, the Italian eventually coming home in four hours 40 minutes and 52 seconds, 42 seconds clear of Carlos Betancur (Ag2R-La Mondiale).

Overall race leader Vincenzo Nibali (Astana) came home 12 seconds further back, alongside his nearest challengers for the pink jersey, Cadel Evans (BMC), Rigoberto Uran (Team Sky) and Mauro Santambrogio (Vini Fantini).

Heading into tomorrow's rest day, Nibali's lead in the general classification remains at 86 seconds over Evans while Uran and Santambrogio are almost three minutes down.

Today's stage only got the green light after race organisers and local officials agreed to shorten the distance by four kilometres, thereby missing the worst of the sub-zero conditions expected at the very summit of the fearsome Col du Galibier.

The stage instead finished at the memorial to former Tour de France and Giro winner Marco Pantani.

After the rain, snow and fog that blighted yesterday's 14th stage, the riders appeared to take the decision to neutralise the day's first climb on the Col du Mont Cenis, with the first serious breakaway not coming until that summit was cleared.

Visconti was in the mix when the break came with 82km to go, pulling away with Stefano Pirazzi, Francesco Bongiorno, Robinson Chalapud, Pieter Weening and Matteo Rabottini.

Weening was the first to attempt a solo break at around 60km out but was reeled in, so it instead fell to Visconti to make the decisive move, hitting the front with a little under 25km remaining and quickly building a cushion.

Visconti took his lead out to almost a minute as he tackled the curtailed ascent of the Col du Galibier.The forecast snow started to fall with three kilometres remaining, but even that could not put Visconti off his rhythm as he came home for a famous victory ahead of a rest day that will be welcomed by all the riders.