Alberto Contador further strengthened his grip on the pink jersey as he took yet more time out of his rivals on stage 18 of the Giro d'Italia.
BMC Racing's Philippe Gilbert raced away to his second stage victory of the Giro but the real action was behind as Tinkoff-Saxo rider Contador added more than a minute to his lead to stand 5 minutes 15 seconds clear of closest rival Mikel Landa Meana of Astana with three stages to go.
The Spaniard attacked on the ascent of Monte Ologno, the major climb of the day, as Landa Meana and Astana team-mate Fabio Aru were caught up behind a crash, giving Contador a measure of revenge for Astana's ultimately fruitless decision to join a Katusha attack after he suffered a mechanical on Wednesday's stage 17.
Contador was able to make his move pay - even as he suffered a dropped chain midway up the climb - as he hooked up with Cannondale-Garmin's Ryder Hesjedal to push to the finish, with the pair opening up an advantage of more than two minutes at one point.
They crossed the line a little over six minutes after Gilbert but crucially 73 seconds ahead of the main group of general classification contenders, giving Contador a huge dollop of insurance ahead of two more mountain stages, and lifting Hesjedal into ninth place overall.
The 170km stage, largely flat before the category one Monte Ologno, saw a large breakaway group go clear early on and as they approached the foot of the mountain, it was clear the stage winner would come from the break.
The group splintered on the climb, but the leading quartet squabbled over who should take their turn and Gilbert chose his moment to sail past them on the descent, immediately opening up a huge gap. The Belgian was so comfortable, he began his celebrations more than two kilometres from the finish.
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