Movistar rider Richard Carapaz surged to the top of the Giro d'Italia's general classification standings after climbing to victory at Stage 14's summit finish, bringing an end to UAE Team Emirates' eight-day hold of the pink jersey.
The 25-year-old Ecuadorian edged ahead of Team Jumbo-Visma's Primoz Roglic in the standings after breaking from the chief contenders on the Giro's toughest hill yet.
"I was thinking just now, it seems only yesterday that I was at home in Ecuador playing on a toy bike. Now I'm here wearing the Maglia Rosa," said an elated Carapaz.
"We'll try and keep the jersey and defend it all the way to Verona."
Britain's Simon Yates was second after attacking on the last kilometre, gaining some redemption for earlier disappointments and climbing to ninth overall, 5min 28sec off the lead.
New leader Carapaz said there was no problem in his team where Mikel Landa would normally be seen as the team leader and who stands fifth at 2min 50sec, and was instead in dreamland after winning his second stage in this year's Giro.
"I worked so hard for this, it's a real dream come true," Carapaz said at the winning post. "I felt good this morning. We knew the altitude was good for me. I gave it everything because I knew the entire Giro was at stake.
"The 30 seconds I gained on the penultimate climb were enough to allow me to build the lead I needed."
Man-to-beat Roglic and two-time winner Vincenzo Nibali kept a close eye on each other all day with the Italian testing the Slovenian with a daredevil descent on the penultimate climb the Colle San Carlo.
It was on that hill that overnight leader, Jan Polanc, ran out of gas and gave up the pink jersey and lost almost eight minutes on the day.
It signalled the end of eight straight days in which UAE Team Emirates held the pink jersey, first through Italian Valerio Conti, who took the lead after Stage 6. Polanc then took the lead after Stage 12.
“On the first climb of the day I was good, but then I struggled," Polanc said. "Valerio and I tried hard to limit the gap, but I must say goodbye to the pink jersey.
"The Giro d'Italia is not over though, we will try to seize future opportunities and achieve some more good results for the team."
Carapaz's win - his second of the Giro after a surprise bunch sprint triumph in stage four - and the show of power with which it was achieved, marks him out as a contender after he came fourth in the Giro last year.
He now leads Roglic by seven seconds, while Nibali is third at 1min 47sec.
Sunday's stage is one of the longest on the Giro at 232km, starting with a 160km flat section before the race swings into a series of short but challenging climbs and descents which pundits feel may suit Nibali.
