Italian Fabio Aru won the 15th stage of the Giro d'Italia on Sunday as overall leader Rigoberto Uran extended his lead over Cadel Evans to just over a minute after another demanding day in the mountains.
Astana rider Aru, who now is fourth overall and a credible contender, attacked in the last part of the final climb of a 225km trek from Valdengo and beat Fabio Andres Duarte by 21 seconds while fellow Colombian and pre-race favourite Nairo Quintana finished third one second further back.
Colombian Uran, who struggled a bit on Saturday, suffered again but took fifth place and still extended his lead over second-placed Australian Evans, the 2011 Tour de France champion, from 32 seconds to 1:03.
Poland's Rafal Majka stayed third 1:50 off the pace with Aru and Quintana 2:24 and 2:40 off the pace respectively.
Italian Domenico Pozzovivo, one of the attackers on Saturday, could not sustain the pace in the finale and dropped to sixth overall.
The peloton is having a rest day on Monday before going through four more mountain stages, including an individual time trial, ahead of next Sunday's final, flat ride to Trieste.