Hemingway loved to box and to spectate: 'Battles, boxing, bull fights: Ernest Hemingway was there, at ringside, celebrating the cult of manhood and danger.' Another website states: 'Hemingway [...] had an aptitude for physical challenge that engaged him through school, where he both played football and boxed. Because of permanent eye damage contracted through numerous boxing matches, Hemingway was repeatedly rejected from service in World War I. Boxing provided more material for Hemingway's stories, as well as a habit of likening his literary feats to boxing victories.'
Michael Reynolds also picks up on this ability to channel his passion and perception into convincing writing, whether he was actually party to the experience or not. Citing one of Hemingway's news pieces on trout fishing, Reynolds comments: 'Their correspondent was not a mere tourist watching professional fisherman; he was a brother to them, his back aching with theirs at their heavy trade. Hemingway became so proficient in creating this kind of illusion that later readers and critics were certain he lived the experiences described in his fiction.' (Michael Reynolds, Hemingway the Paris Years, New York and London: W. W. Norton and Company, 1999, p.10)
Boxing, as with many other competitive sports in the 1920s, was enjoying a rise in popularity in both Europe and the US.
Jack Dempsey was one of the most celebrated boxers of the time, however, Stephen J. Gertz points out that 'there was one person in Paris that year whose desire to get in the ring with Dempsey would not be indulged. Ernest Hemingway was a threat. Not to Dempsey but to himself.'