Tennis is the loneliest sport.

Agassi’s line captures the psychological isolation built into elite tennis: once the match begins, there are no teammates to share responsibility, absorb momentum swings, or offer real-time help. The player is alone with their body, tactics, and nerves, while every error is publicly visible and immediately consequential. The remark also points to the sport’s emotional paradox—played before crowds and cameras, yet experienced as a solitary struggle inside one’s own head. In Agassi’s case, the sentiment resonates with his well-known accounts of pressure, expectation, and ambivalence about the game, making “loneliest” as much about inner experience as about the rules of play.