Alberto Contador of Tinkoff-Saxo has ridden one of the Grand Tour stages of his life to conquer the Mortirolo, starting the climb nearly a minute behind Fabio Aru after puncturing but finishing the ascent almost two minutes ahead of the Astana rider.
The latter's team mate, Mikel Landa, won the stage to move into second place overall - 4 minutes 2 seconds down on the leader - crossing the line a little more than 30 seconds ahead of LottoNL-Jumbo's Steve Kruijswik and Contador, with Aru almost two and a half minutes further back.
Seen as one of the toughest climbs in professional cycling, the Mortirolo will be forever associated with the 1994 duel between Marco Pantani and Miguel Indurain, the stage, like today’s, finishing in Aprica.
Today, however, it was a Spanish rider who prevailed over an Italian on that ascent. Aru had started the day 2 minutes 35 seconds behind Contador after handing back the maglia rosa after just 24 hours in it following Saturday's individual time trial.
On the descent from the first passage of the finish line to the foot of the Mortirolo on today’s 174km stage from Pinzolo, the Sardinian was given hope of reducing the deficit as Contador punctured and found himself 50 seconds back.
With 2012 winner Ryder Hesjedal of Cannondale-Garmin out front on his own, the chasers were split into groups, the first led by Katusha, the second by Astana, and the third by Tinkoff-Saxo as they desperately tried to get Contador back across to Aru.
The race leader was on his own by the time he reached the bottom of the 12.2km ascent of the Mortirolo, which has ramps of up to 18 per cent. Blasting past riders who had been ahead of him as they fell back, Contador reached the front group, including Aru, halfway up.
Almost immediately, the Tinkoff-Saxo rider went on the attack, his Astana rival unable to go with him as he followed a move from LottoNL-Jumbo’s Steve Kruijswijk.
Instead, it was Aru’s team mate, Mikel Landa, who went with Contador and the Dutchman, and they would be the trio to contest the stage win.
As he tried to limit his losses on the descent ahead of the second and final 14km climb to Aprica, there was more bad news for Aru as he, too, punctured, immediately taking a spare bike from his team car which was close at hand. He fell further behind on the last climb, though, and now lies third overall.
On that last ascent, Kruijswijk attacked with a little more than 4km remaining, but Landa - who had sat behind the LottoNL-Jumbo rider and Contador until now - countered immediately and rode off to take his second stage win in succession, the first man in this year's race to win more than one stage.
After the stage, Landa admitted that Astana had ridden hard to try to distance Contador after he punctured, an apparent violation of the unwritten rule in the peloton that no one should try to take advantage of a race leader's mechanical problems.
Some noted on social media though that Contador hadn't waited for Andy Schleck following the infamous 'chaingate' incident at the 2010 Tour de France as he took the yellow jersey from the Luxembourg rider - although Schleck would get the title once the Spaniard was stripped of it after testing positive for clenbuterol.
Landa added: "It was a really beautiful day for me, perhaps even better than Sunday. We saw that Alberto had a problem, and Katusha went full gas, so we worked with them.
"On the Mortirolo, Fabio Aru wasn't feeling good and he told me to go with Contador and Kruijswijk.
"Today I really proved that I can be one of the strongest riders on the climbs, and we still have several uphill finishes left.
"As a team, we will have to stick together and stay attentive, because what happened to Contador today could happen to one of us."
Contador, who grew up idolising Pantani, may not have won the stage but he has now carved his name into the history of the Mortirolo.
He said: "It was a very hard day, an incredible stage. Cycling isn't mathematics: I had a puncture on the descent, Ivan Basso gave me a wheel, but ahead they were going at full speed, and it was impossible to close the gap immediately.
"It was hard for me, but I'm very happy with the time gaps now. I would have liked to have helped Steven Kruijswijk, but it was not to be. To Mikel Landa, I can only say: chapeau. These are the stages that people remember."
Simon has been news editor at road.cc since 2009, reporting on 10 editions and counting of pro cycling’s biggest races such as the Tour de France, stories on issues including infrastructure and campaigning, and interviewing some of the biggest names in cycling. A law and languages graduate, published translator and former retail analyst, his background has proved invaluable in reporting on issues as diverse as cycling-related court cases, anti-doping investigations, and the bike industry. He splits his time between London and Cambridge, and loves taking his miniature schnauzer Elodie on adventures in the basket of her Elephant Bike.