When Jake questions Joey about Vickie, Joey reminds him that he is a married man. At the neighborhood swimming pool one day, Jake spots blonde, fifteen-year-old Vickie Thailer, who piques his interest and passion. Later, when Salvy comes to watch Jake in a sparring match with Joey, Jake becomes so angered by Salvy's presence that he pummels Joey. Suddenly hostile, Jake provokes Joey into hitting him in the face. Once Joey mollifies his enraged brother, the mercurial Jake laments that his small, girlish hands limit his ability to rise to the top. Nevertheless, Joey promises to present Salvy's offer to Jake, and proceeds to his brother's dreary, run-down apartment, where Jake is in the middle of a screaming match with his wife Irma. Although Joey agrees with Salvy, he observes that his stubborn brother, whom he affectionately calls 'Jack,' has 'a head like concrete' and insists upon remaining independent.

Following Jake's defeat, Salvy Batts, who works for boxing racketeer Tommy Como, informs Jake's brother and manager Joey that an association with Tommy could advance Jake's career.

In 1941, at a boxing match in Cleveland, Ohio, pandemonium breaks out when Jake La Motta, an up-and-coming young boxer, loses a decision to Jimmy Reeves, suffering his first loss and igniting a brawl in which audience members are trampled underfoot.

The raging bull