I define humility as a virtue that includes both proper self-assessment and a self-lowering other-centeredness. I then argue that humility, so understood, is a virtue in the context of sport, for several reasons. Humility is a component of sportspersonship, deters egoism in sport, fuels athletic aspiration and risk-taking, fosters athletic forms of self-knowledge, decreases the likelihood of an athlete seeking to strongly humiliate her opponents or be weakly humiliated by them, and can motivate an athlete to achieve greater levels of excellence in her sport. In the context of team sports, humility can contribute to an athlete being a better teammate, foster unity amidst diversity within a team, and contribute to the overall moral and athletic excellence of a team. I also argue that an individual who is truly the world's greatest athlete can know and communicate this truth, while remaining humble.