It was billed 'The Fight of the Century'. The date was March 8, 1971, the venue Madison Square Garden in New York City. Two undefeated champions, Joe Frazier and Muhammad Ali, meeting for the first time.

On the other side of the rope, an unlikely line-up of stars were on media duty. Burt Lancaster was commentating, and he was joined by LIFE magazine's reporter/photographer duo: Norman Mailer and Frank Sinatra.

AP file Sizing up a possible photograph (and being photographed at the same time) at Madison Square Garden, March 8, 1971, is film star Frank Sinatra, center. The movie star was photographing ringside for Life Magazine at the Muhammad Ali - Joe Frazier heavyweight title bout.

Frank Sinatra / LIFE The cover of Life Magazine with photo taken by Frank Sinatra

"I got some good pictures that night, but I kept watching Frazier putting his head too far out for Ali to punch it," Sinatra later recalled in a conversation with Bill Gallo, a sportswriter with The New York Daily News. "He was defying Ali, and I said to the newspaper guy next to me: 'He may win, but if he keeps that up, he's going to the hospital, taking all those punches.' "

Frazier defeated Ali in 15 rounds.

As pointed out by the blogger Tim O'Shea, Sinatra's skills as a photographer were not universally appreciated. LIFE's letters page of April 9, 1971 contained a critical missive from Robert W. Kelley of Seattle, Wash.:

Sirs: I'm so mad I could chew nails and spit tacks. I've been a professional news photographer 34 years (about 18 on LIFE's staff) and what irks me is your cover .. It was obviously selected because Frank Sinatra took it, rather for any photographic excellence. In fact, it was a bad picture. What millions of LIFE readers wanted to see was Frazier's fist firmly implanted against Muhammad Ali's mouth.

What do you think? Would Sinatra have been better off sticking to the day job?

Related content: