While other classics rider and sprinters climbed off to escape the terrible weather conditions and steep Le Marche hills, Sagan used his range of talents to stay with the overall contenders on the climbs, go clear with Vincenzo Nibali on the rain-soaked descent and then win the stage without barely opening up his sprint finish.
As he crossed the finish line, Sagan kissed his biceps in another of his original celebration gestures.
"I kissed my biceps because the climb was so hard that I needed my arms more than my legs, they were more in pain than my legs," he explained with a cheeky grin and laugh in the post-stage press conference.
"Today was similar to a Classic in Belgium. We've raced four hard days before this, so it was a very hard day. It was difficult on the 30% climbs with the rain. If you got out of the saddle, you wheel slipped and so I had to ride sitting down and use your power."
Sagan revealed that Nibali had hinted he would attack on the final climb of Sant' Elpidio di Mare, asking his former teammate if he would go with him.
"I was more motivated yesterday to be honest but the long climb hurt my legs for the final short climbs and then the GC riders attacked hard and dropped me."
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Sagan's second stage victory in tough conditions after another six hours of racing only reinforced opinion that he is the number one favourite for Sunday's Milano-Sanremo, despite still only being 23.
Sagan's performances have left other teams and riders left scratching their heads to try and find a way to beat him. Sagan's superiority seems so great that even he's started to be embarrassed by it.
"I'm a favourite every year and then never win. We'll see what happens this year," he said.
"Milano-Sanremo is difficult to win. If you make just one mistake, if you crash, if it rains or of the bunch splits, anything can happen. You can't plan before the race, in cycling you've got to go with your instinct. In the last few years the rider who won was not 10 ten favourites.
However when asked by Cyclingnews how he would beat a rider like Peter Sagan, he couldn't stop himself from saying jokingly: "Perhaps it's better if they don't start..."
Stephen is one of the most experienced members of the Cyclingnews team, having reported on professional cycling since 1994. Before becoming Editor-at-large, he was Head of News at Cyclingnews. He has previously worked for Shift Active Media, Reuters and Cycling Weekly. He is a member of the Board of the Association Internationale des Journalistes du Cyclisme (AIJC).
