Jack Dempsey vs. Luis Ángel Firpo was a boxing match and one of the most significant events in sports of the era.

After going 4–0 in 1922, Firpo began 1923 at Madison Square Garden knocking out former title challenger Bill Brennan in the 12th round with a right.

"Dempsey never hit me any harder than this fellow," said Brennan, adding that he couldn't wear his old hat because his head was too swollen.

[1] Firpo knocked out former heavyweight champion Jess Willard in front of 100,000 spectators, a world record for boxing attendance at the time.

[3] The match was at the Polo Grounds, normal capacity 55,000, but an additional 20,000 seats were constructed bringing the total to 75,000 for the fight,[4] later expanded to 83,000.

The police estimated that 150,000 people showed up, including a mass extending a quarter mile in every direction around the arena.

[6] Firpo was floored seven times in the first round of the bout, before he trapped Dempsey against the ropes and launched a combination that sent the champion out of the ring.

The referee, Johnny Gallagher, was still supposed to prevent the fighter from scoring the knockdown by standing directly over his floored opponent.

Dempsey later lost his Heavyweight title to Gene Tunney in two equally historic bouts (see: The Long Count Fight).

Ultimately, John Ruiz, an American of Puerto Rican descent, became the first boxer of Hispanic and of Latin American descent to win the world Heavyweight title, beating Evander Holyfield in 2001 for the World Boxing Association's version of the title.

In 1935, the New York Daily News asked five prominent fighters and others involved in boxing to name the greatest ring battle they ever saw.

Three of them- light-heavyweight champion Bob Olin, trainer Doc Robb and Madison Square Garden announcer Clem White- responded with the Dempsey-Firpo fight.

Moreover, challenger Rocky Balboa floors champion Apollo Creed at the very start of the fight, just as Firpo did to Dempsey.