Mauro Santambrogio took the stage victory but overall leader Vincenzo Nibali was the big winner as the poor weather dominated stage 14 of the Giro d'Italia.
Organisers were forced to remove the day's major climb as snow, rain and fog hit, but Santambrogio and Nibali emerged from the mist at the mountain-top finish after launching a late attack from the peloton to reel in the remnants of an early breakaway.
Nibali was content to follow the Vini Fantini-Selle Italia rider across the line, knowing that those closest to him in the GC standings were far behind down the road.
Cadel Evans, who began the day 41 seconds behind Nibali in second place, crossed the line 33 seconds later, while Team Sky's Rigoberto Uran also lost time as he finished 30 seconds back.
With the bonus seconds factored in, that leaves Evans second, one minute and 26 seconds down in the GC, while Uran dropped to two minutes and 46 seconds back in third.
The stage win saw Santambrogio put himself in the discussion too, as he moved from sixth in the GC to fourth, one second behind Uran.
There had been little surprise earlier in the day when organisers confirmed they had been forced to divert the course around the category two climb to Sestriere due to the continuing poor weather, extending the distance from 168 kilometres to 180km.
Katusha's Luca Paolini, Bardiani's Sonny Colbrelli, Lampre's Daniele Petropelli and Omega Pharma-Quick Step's Matteo Trentin led the early breakaway and had forged a lead of almost 10 minutes, knowing they would need plenty of time in hand if they were to hang on during the final climb.
As the race moved inside the final 10km it still looked as if the stage winner would come from that group but the peloton was closing fast and several riders launched attacks to try and make up ground.
With the leaders in sight, Nibali made his move late with barely a kilometre left and Santambrogio went with the Astana man.
The pair came through the fog alone before Carlos Betancur finished third, eight seconds back, and then the long wait for Samuel Sanchez Euskaltel, Uran and Evans.
Robert Gesink and Michele Scarponi, the 2011 Giro winner, had begun the day fourth and fifth respectively in the GC standings, but their challenges suffered on the final climb as they finished well off the pace.
Scarponi held fifth but fell three minutes 53 seconds back while Gesink disappeared from the top 10 all together.
Attention now turns to tomorrow's stage 15, scheduled to be a 149km run to the famous Col du Galibier climb, with major changes expected to the route due to the poor weather.