Sagan won the 257.5-kilometre Worlds, the first in the Middle East, in a sprint ahead of Brit Mark Cavendish and Belgian Tom Boonen. The rainbow jersey adds to the one he won last year in Richmond, USA.
"I'm still in shock," Sagan said when he rolled to a stop and let down his long hair.
"When it split in crosswinds, I was last to make it to the front group."
Sagan will ride for team Bora-Hansgrohe next year after two years with trade team Tinkoff. However, his national team was out-numbered in the Persian Gulf. Great Britain, Belgium, Italy and other top teams counted nnin. Slovakia only qualified for three spots: Sagan, his brother Juraj and Michael Kolar. The two will also join Sagan in moving to team Bora next year.
They made sure that Sagan made the split when the group broke into cross-winds on the desert roads north of petroleum rich capital city of Doha. A small group of around 25 competed for the sprint after finishing the seven circuits on the Pearl Island.
"My brother was also in the first group but when he took water, he was dropped," added Sagan. "Thanks to Michael Kolar, who worked for me all day and supported me.
"I thought, I'm going to do the sprint, but ‘we'll see.’ [In the final metres], I have to go. I was a little bit back [in the group], I thought I have to go now.
“I was luckily that [Italian Giacomo] Nizzolo didn't close the gap when I was coming up. If he closed on me we were going to crash because I wasn't going to brake. I'm very happy for that, it's unbelievable."
Sagan briefly hugged a group of fans on the side of the barriers waving the Slovakian flag. They were part of a limited number along the Qatari roads in this Worlds.
"I have the biggest fan group here and I felt it. Thanks to everybody for that and to Slovakia," Sagan explained.
"Thanks to the family. My father is here, my wife. And my friends from my home town came here and supported me. Thanks for everything, I had to win today."
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