In 1929 Fleischer acquired sole ownership of the magazine, which he led as editor-in-chief for fifty years, until his death at Atlantic Beach, New York in 1972.

[2] In 1954, Fleischer was involved with the "Bare-footed Title Fight", a world championship bout fought in Thailand's open air Chulalongkorn Stadium during a tropical monsoon.

Thai General Pichai invited Fleischer as a special guest to his homeland, as a way to ensure that the World Bantamweight Championship bout, between champion Jimmy Carruthers of Australia and challenger Chamroen Songkitrat, would follow the international boxing rules.

In an effort to better their traction in the flooded ring, this became the first recorded match in modern world boxing history where the fighters removed their footwear.

Fleischer was seated at ringside on May 25, 1965, at the heavyweight championship rematch between Muhammad Ali and Sonny Liston in Lewiston, Maine to report on the contest for The Ring.

Fleischer yelled at referee Jersey Joe Walcott (the former heavyweight titlist) to inform him that the knockdown timekeeper's count had reached ten with Liston still on the canvas.

As part of the antiwar movement in the United States during the Vietnam era, Muhammad Ali lost his world heavyweight crown in the eyes of most American boxing commissions when he refused to be inducted in the U.S. Army.