Charles L. “Sonny” Liston became the world heavyweight champion in 1962 after knocking out Floyd Patterson in the first round, repeating the knockout the following year in defense of the title.
Liston lost the title in 1964 to Muhammad Ali midst claims that he had been drinking heavily the night before the fight and had entered the bout with a lame shoulder. In a 1965 rematch with Ali, Liston suffered an unexpected first-round knockout that led to unresolved suspicions of a fix.
One of my college friends, Joe Rocco, drove hundreds of miles from upstate NY to Lewiston, Maine to see the fight. He had bought some beers and just got to his seat when the 1st round started. He passed out the beers to guys sitting behind him, and when he turned back to watch the fight, he saw Liston lying on his back. Never saw a punch.