[6] As a freshman for the Spiders in 1993, Casey had a .386 batting average, a .447 on-base percentage (OBP), and a .526 SLG, with two home runs.

[13] Casey began his professional career with the Watertown Indians of the Class A-Short Season New York–Penn League, where he batted .329 with two home runs.

On June 18, the Indians promoted Casey to the Buffalo Bisons of the Class AAA American Association after batting .386 with 19 doubles, 10 home runs and 66 RBIs in 62 games with Akron.

Casey won the Lou Boudreau Award as the Cleveland Indians' top minor-league position player, at the conclusion of the 1997 season.

[16] On April 3, 1998, Casey was hit in the eye with a ball thrown by teammate Damian Jackson during batting practice, resulting in an orbital fracture, and subsequent surgery.

[20] On May 19, 1999, the Reds defeated the Colorado Rockies in a 24−12 final, tied for the fourth-highest run-scoring output in MLB history.

[22] During his tenure in Cincinnati, and later in Pittsburgh and Detroit, Casey was regarded as approachable and friendly, and his nickname, "the Mayor", comes from his reputation for chatting casually with every runner who makes it to first base, and from his very public charity work.

This tied him with A. J. Pierzynski for the record of most grounding in double plays by a National League left-handed batter in a season.

[citation needed] On July 31, 2006, the Pirates traded Casey to the Detroit Tigers for minor league pitcher Brian Rogers.

[28] During the 2006 American League Championship Series against the Oakland Athletics, he partially tore his left calf muscle in Game 1.

[31] Casey credits his Christian upbringing in Pittsburgh's affluent Upper St. Clair suburb for his generosity.

[36] He was on the disabled list from April 26 through May 12, and returned as a significant part-time player, finishing the regular season with a .773 OPS on 199 at-bats in 69 games.

[4] On July 3, 2009, Casey sat in for Red Sox color commentator Jerry Remy, calling the first game for his old team.

On January 14, 2011, the Reds announced that Casey would do color commentary for 15 telecasts on Fox Sports Ohio during the 2011 season.

[40] With Conan O'Brien, Casey is a founder of Labels Are For Jars,[41] an innovative anti-hunger organization based in Lawrence, Massachusetts.

[43] Casey was inducted to the Cincinnati Reds Baseball Hall of Fame (along with Dan Driessen and John Reilly) on June 23, 2012.

[44] Casey resides in Upper St. Clair Township, Pennsylvania, with his wife, Sarah, and four children, Andrew, Jake, Carli, and Jillian.