Jan Polanc conquered Mount Etna to claim stage four of the Giro d'Italia in comfortable fashion on Tuesday, while Bob Jungels moved into the overall lead.
Following Monday's rest day, riders faced a 181km route that culminated in a gruelling climb to reach a finish line that sat a dizzying 1,892 metres above sea level.
Polanc attacked from the off and, after breaking clear with Janse van Rensburg heading into the final 25km, he eventually found himself racing alone and opening up a lead of almost four minutes.
And that cushion served the Slovenian well as he crossed the line 19 seconds clear of second-placed Ilnur Zakarin, who survived an early crash, with Team Sky's Geraint Thomas a further 10 seconds back in third.
Jungels finished just behind Thomas to clinch the Maglia Rosa from Quick-Step Floors team-mate Fernando Gaviria.
"It was amazing today," Polanc, whose last stage win came in 2015, told reporters. "Probably nobody expected the break to arrive to the finish, we didn't have big gap before last climb, and we were four all day, so it was difficult but I'm very happy.
"After 2015, to repeat the victory on the first mountain stage, it's incredible for me - I'm really happy. Thanks to my team, my family, and all those who supported me. I can't describe a moment like this.
"The climb was difficult with a constant headwind, especially after a long break. It was probably the hardest day of my life."
GOOD DAY/BAD DAY
It was a strong day for some of the pre-race favourites, with Zakarin, Thomas and Thibaut Pinot all tipped to do well in this year's Giro and finishing in the top five on Tuesday.
Not such a great day for BMC's Rohan Dennis, however. The Australian was forced to pull out midway through stage four as a result of injuries sustained in a crash on Sunday.
1. Jan Polanc (UAE Team Emirates): 4:55:58
2. Ilnur Zakarin (Team Katusha-Alpecin): +0:00:19
3. Geraint Thomas (Team Sky): +0:00:29
4. Thibaut Pinot (FDJ): +0:00:29
5. Dario Cataldo (Astana): +0:00:29
1. Bob Jungels (Quick-Step Floors): 19:41:56
2. Geraint Thomas (Team Sky): +0:00:06
3. Adam Yates (Orica-Scott): +0:00:10
1. Andre Greipel (Lotto Soudal): 81pts
2. Daniel Teklehaimanot (Dimension Data): 74pts
3. Fernando Gaviria (Quick-Step Floors): 72pts
KING OF THE MOUNTAINS
1. Jan Polanc (UAE Team Emirates): 43pts
2. Daniel Teklehaimanot (Dimension Data): 22pts
3. Ilnur Zakarin (Team Katusha-Alpecin): 18pts
Riders will be grateful to spot a relatively flat 159km route from Pedara to Messina on the schedule for Wednesday.