It is Mike Tyson when he was fighting with Trevor Berbick
He became the youngest heavyweight champion in history.
Mike Tyson hold the record for the youngest heavyweight champion of the world at 20 years, 4 months and 22 days old
prince naseem hamed
Iron Mike Tyson was the youngest heavy weight champion ever at 20 years old.
The current F1 world champion is Sebastian Vettel from Germany. He is the youngest ever world champion.
Vitali Klitschko of the Ukraine has been the World Boxing Council heavyweight champion since October 2008.
Unfortunately there is no undisputed heavyweight champion.