Casey at the Bat, subtitled "A Ballad of the Republic Sung in the Year 1888", is a Baseball poem written by Ernest Thayer. First published in 1888, it was popularized by DeWolf Hopper in many Vaudeville performances. The poem is a fictional account of a team from Mudville, who are sure they can win if they can stay in the game until Casey is up to bat. The over-confident Casey refuses to swing at the first two pitches, which are strikes, and on the last pitch the mighty Casey strikes out.
- Ernie hangs a pennant for Mudville (the team Casey played for) in his room in a Sesame Street sketch.