Slovakian road cyclist Peter Sagan is perhaps the sport’s most beloved personality, an easygoing world champion with rock god hair who not long ago filmed a shot-for-shot remake of the final scene of the movie “Grease,” with his wife, Katarina, starring in Olivia Newton-John’s Sandy role, and Sagan playing John Travolta’s Danny Zuko, lip-syncing merrily to “You’re the One that I Want.”

You have to see it to believe it. It’s, to use the scientific term, amazeballs.

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