Darry fights his old "buddy" Paul Holden during the rumble between the greasers and the Socs in chapter nine. Darry and Paul had been friends and peers in high school, both playing on the football team. While Darry had to go to work after high school, Paul was able to attend college. The difference in outcomes for the two boys illustrates the contrast between the greasers, who come from lower class backgrounds, and the Socs, who are upper middle class. Even though Darry was Paul's equal in high school, both academically and athletically, he is relegated to a life of backbreaking labor while Paul attends college with the anticipation of advancing toward the same privileged life of his parents. Darry has to give up his dreams of college, despite having won a scholarship, and go to work to support his brothers after the death of the boys' parents. Ponyboy suggests that Darry now hates Paul, partly out of jealousy, but also because Darry knows that he is better than just his label as a greaser and that life has been unfair to him. In a bit of retribution, Darry winds up beating Paul in the fight and the greasers win the day.
Paul Holden is a soc who was on the football team that Darry quit after his family fell apart, forcing him to take care of his brothers. Both boys are equally good athletes, and both had a degree of respect for one another on the football field and in school. However, due to the Shakespearean nature of the Greaser-Soc feud, the two boys who were once near-friends are forced to face off against each other in combat. This is a moment of irony in the novel, among many others.
Darry and Paul Holden fought in the rumble. The rumble was supposed to be a moral lesson for the characters.