Alpecin Phoenix's Oscar Liesebeek regretted missing a once-in-a-lifetime opportunity when he was passed by Couveka Assos' Victor Kampenaerts in the final of stage 15 of the Giro d'Italia on Sunday.

The Dutchman was the only rider to break away from the early breakaway group and stick with the UCI world hour record holder on the final hill of the 147km stage, which was set around the eastern border with Slovenia.

Campenaerts opened up a gap on the rain-soaked final climb before the finish before Liesebeek made it to the sprint on the cobbled Gorizia. Liesebeek was looking to add a second stage win to teammate Tim Merlier's second stage victory.

"I think it was a once-in-a-lifetime opportunity," he recalled shortly after the loss.

"I just made a mistake. Of course, he was really strong too; it's hard to say nice things after 15 days. I'm really disappointed right now."

Riesebeek, 28, turned pro from room pot in 2017 and joined Alpecin Phoenix last season, but so far he has only 2.2 places in last year's Tour Bitowa Warszawska on his hands. Tonight, his second place in his debut Grand Tour will be filed alongside his runner-up finish in the 2018 Druivenkoers Ovelaise.

The second half of the stage saw the riders hit by heavy rain as they tackled the fourth class 4 mountain of Gornje Cerovo, just across the Slovenian border.

Lisebeck said it was a dangerous finale, as he and Dario Cataldo (Movistar), Bauke Mollema (Trek-Segafredo), Nikias Arndt (Team DSM), and Kampnerts escaped from the remaining breakaway group, but his mind was clearly was toward the events of the last few meters.

"The last 10km were really slippery. It was unbelievable. There were risks, but I grabbed the handlebars and tried to come back in the last kilometer."

"Then I tried to sprint off his wheel. I think I got back in the saddle too fast and then came the campenaerts.