Sagan won three sprints so far in the 2018 Tour to build up an almost insurmountable green jersey lead. His rivals, the ones who could survive the mountains so far, have trouble finding ways to manage the three-time world champion when the finish line nears.
"Sagan is the complete package," Sonny Colbrelli (Bahrain Merida) told Cycling Weekly.
"It seems as though maybe he won't be able to do it at times, but instead, he comes through the gaps at the last moment. He has this truly lethal jump. There's a clear reason why he is three times the world champion."
Colbrelli beat Sagan in a Tour de Suisse sprint this June, but it was one of the few if not the only time the Italian could do so. So far in the Tour, he counts two runner-up spots against Sagan.
"When Sagan is in condition, he's a cannibal and wins everything. His name is known around the world for this," Colbrelli said.
"There are not many [weaknesses], I don't know them! Sometimes you can try to jump him early, anticipate him. But if you get the jump, he loses a few pedal strokes and maybe he's not able to win. Almost 10 out of 10 times, though, he's able to fire back when you try.
"You can beat him, for sure, he's not unbeatable. You have to be 100 per cent to have a chance, though."
The Alpine stages took their toll for the big sprinters. The abandons over the last week include Mark Cavendish (Dimension Data), Marcel Kittel (Katusha-Alpecin), Fernando Gaviria (Quick-Step Floors), André Greipel (Lotto-Soudal) and Dylan Groenewegen (LottoNL-Jumbo).
Alexander Kristoff (UAE-Team Emirates), with two Tour stage wins from 2014, remains. However, the Norwegians still struggles with Sagan even with the thinning bunch sprints.
"[Sprinting against Sagan is] difficult, he's fast as a sprinter, but he also wins up hills and climbs very well so he's one of the best cyclists in the history of cycling," said Kristoff. "You see that because he's been world champion three times in a row. He's incredible."
Kristoff sprinted to second in Valence after surviving the Alps. Only one rider could edge ahead – Peter Sagan.
"How do you beat him? You should not ask me, I don't beat him that often!" Kristoff said.
"If I sprint fast enough, sometimes he doesn't manage to come around. He has a really good kick in the last 100 metres always, but if I manage to have a little bit more speed then maybe. Usually he just manages to come around me, but sometimes I manage to hold him behind me. It's some time ago, though, that I could do that."
Kristoff and Kittel often benefit from long sprint outs from their teams and high speeds.
"But then he just sits on the wheel and waits for the last 100 metres," Kristoff added. "That doesn't help. Maybe if I mange to come behind at bigger speed, but he's always in the right spot and it's difficult to beat him."
Time to beat Sagan is running out for Colbrelli and Kristoff. Only two likely sprint days remain, the stage 18 finish in Pau and stage 21 in Paris.
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