Fredrik Dversnes won the fifth stage of the Tirreno-Adriatico on Friday as Filippo Ganna held his overall lead, despite a mechanical failure in the finale that left him trailing the peloton.

Norwegian Dversnes claimed his first-ever World Tour win ahead of star riders like Tom Pidcock and Mathieu van der Poel after spending almost the entire 205km journey from Ascoli Piceno to Pergola as part of a breakaway.

Fredrik Dversnes Reflects On First World Tour Victory

"I'd had a pretty hard, cold two days, so with this (drier) weather today, it turned out to be a good stage," said Dversnes.

"Then in the final climb, I got instructions from my sports director to go all in, and fortunately, it turned out to be good enough. There was a pretty hard kicker up at a kilometer to go, so I wasn't sure if I could win until 500 meters to go."

Filippo Ganna Holds Lead Despite Late Mechanical Issue

Ganna remains 22 seconds ahead of Juan Ayuso in the general classification, but the Ineos rider came very close to losing his lead after his chain broke with less than five kilometers remaining.

The Italian, a two-time time-trial world champion and track cycling specialist, held on to the peloton throughout a long ride full of punchy climbs before nearly slipping out of contention at the last moment.

But he managed to stay with the main bunch until three kilometers to go, where his time was neutralized, allowing him to retain his lead.

"I tried to put the chain back, but it got stuck. I hit the pedal too hard and I smashed it," Ganna told broadcaster RAI.

"I managed to get into the final three kilometers and I held my hand up to take the neutralized time, but it was close."

If Ganna is to keep the blue jersey for the overall leader, he will have to stay with the general classification contenders in Saturday's Queen Stage—a 163km run that ends with a summit finish at Frontignano.

This seems unlikely given his lack of pedigree as a climber, but he said he would give it a go as the final stage is a procession to San Benedetto del Tronto on Italy's Adriatic coast.

"Yesterday and the day before weren't my type of stage either," said Ganna. "I'm going day by day. Let's see tomorrow how I'm feeling."