Australian Jai Hindley said Sunweb's strategy was "perfect" as he won Thursday's gruelling Giro d'Italia 18th stage on the Stelvio pass in the northern Italian Alps to help team-mate Wilco Kelderman take the leader's pink jersey.
Dutch rider Kelderman struggled on the final two climbs but his fifth-place finish was enough to overtake Joao Almeida three days before the race finishes in Milan.
"Winning here is such an incredible feeling," said 24-year-old Hindley.
"It's a big step forward in my career and a double success for the team with Wilco Kelderman now wearing the Maglia Rosa. The tactics were perfect for our team today."
Kelderman took the lead from Portugal's Almeida of Deceuninck Quick-Step who had been in pink for more than two weeks since stage three in Sicily.
Three riders are battling at the top of the overall standings with Hindley 12 seconds behind his teammate and Britain's Tao Geoghegan Hart third 15sec off the pace, after finishing second on the day.
"The hardest stage of my life," said 29-year-old Kelderman.
"We had a goal and we achieved it. Wearing the Maglia Rosa is a dream after so many difficult years, I'm really happy to be leading the overall standings."
Almeida drops to fifth place at 2min 16sec, after finishing the stage in 48th position after the 207km run from Pinzolo to the Cancano Lakes in the Stelvio National Park.
Hindley and Geoghegan Hart outpaced Kelderman with 8km to go towards the summit of the snow-capped Stelvio at an altitude of 2,758m.
Kelderman was overtaken by Spaniard Pello Bilbao and Dane Jakob Fuglsang on the final 8.7km climb with a gradient of 6.8 percent to the Cancano Lakes.
Hindley crossed just ahead of Ineos' Geoghegan Hart with Spaniard Pello Bilbao of Bahrain-McLaren third at 46sec.
It was a first WorldTour success for Hindley who had already impressed last Sunday at Piancavallo in the Dolomites.
Friday's 19th stage returns to the plains with a 253km run from Morbegno to Asti in Piedmont.
Results and standings from the 18th stage of the Giro d'Italia on Thursday, a 207km ride from Pinzolo to Cancano:
Stage results
1. Jai Hindley (AUS/Sunweb) 6hrs 03min 03sec, 2. Tao Geoghegan Hart (GBR/INE) same time,3. Pello Bilbao (ESP/BAH) at 46 seconds, 4. Jakob Fuglsang (DEN/AST) 1min 25sec, 5. Wilco Kelderman (NED/SUN) 2:18, 6. Patrick Konrad (AUT/BOR) 4:04, 7. Joao Almeida (POR/DEC) 4:51, 8. Vincenzo Nibali (ITA/TRE) 4:51, 9. Hermann Pernsteiner (AUT/BAH) 4:51, 10. Fausto Masnada (ITA/DEC) 4:55, 11. Rafal Majka (POL/BOR) 6:43
Overall standings
1. Wilco Kelderman (NED/SUN) 77hrs 46mins 56sec, 2. Jai Hindley (AUS/SUN) at 12sec, 3. Tao Geoghegan Hart (GBR/INE) 15, 4. Pello Bilbao (ESP/BAH) 1:19, 5. Joao Almeida (POR/DEC) 2:16, 6. Jakob Fuglsang (DEN/AST) 3:59, 7. Patrick Konrad (AUT/BOR) 5:40, 8. Vincenzo Nibali (ITA/TRE) 5:47, 9. Fausto Masnada (ITA/DEC) 6:46, 10. Hermann Pernsteiner (AUT/BAH) 7:23, 11. Rafal Majka (POL/BOR) 7:28