The three stories that make up the volume are a reflection of the interest that the North American writer professed towards pugilism, a sport he was a fan of in his youth and, already in his maturity, a chronicler in the graphic press.

"El Combat" ("The Game") was serialized between April and May 1905 in The Metropolitan Magazine. This short novel recreates an event that London witnessed: the fatal outcome of a boxer at the West Oakland Club.

"Un bistec" ("A Piece of Steak"), written between April and May 1909, cost The Saturday Evening Post $500 and was published in November of the same year. The story tells the story of Tom King, a veteran boxer, whose family is plagued by hunger. The night of the fight, his wife fasts and sends the children to sleep without dinner so that Tom can have a bowl of porridge and face Sandel, a young and rising fighter. "A steak" is considered among the best boxing stories ever written.

"El Mexicano" ("The Mexican") was sold for $750 to The Saturday Evening Post and published in August 1911. London wrote the story at the start of the Mexican Revolution, drawing inspiration from the life of Joe Rivers, a pseudonym for José Ybarra, a boxer in exile who donated the proceeds from his fights to the revolutionary cause.

In these stories, London develops all his ability to portray with exemplary clarity what his characters hear, feel and see, sensing their emotions and conveying to the reader, through sober writing, the feeling of anxiety, danger and despair. The time he was questioned about his style, London reported that his method was simply to "discover the true wonder of things." Throughout his work, he underlies a strong, objective and profound criticism of Western culture. The reader of Marx, Darwin and Nietzsche, the tramp on the Oakland docks, the amateur boxer, the gold prospector in Alaska, understood that society was no less harsh and cruel than nature. And on that conviction he founded his literature