Jeremy David Affeldt is an American baseball professional relief pitcher for the San Francisco Giants of Major League Baseball. He throws and bats left-handed. He has also played for the Kansas City Royals, Colorado Rockies, and Cincinnati Reds. Affeldt was a third-round draft pick by the Kansas City Royals in 1997. He made the team in 2002, and he started part of the year for them. Affeldt almost was the first starter for the Royals in 2003, but he lost a coin toss by Royals' manager Tony Peña. He did not remain in the starting rotation for the entire year, however. In 2004, Affeldt started the year in the rotation, but he was named the Royals closer in May. Affeldt started 2005 as the closer, but he was injured and Mike MacDougal reclaimed the role. In 2006, Affeldt again made the Royals' starting rotation, but he was moved to the bullpen after he struggled as a starter. He was traded to the Colorado Rockies at the trade deadline. In 2007, he was a member of the Rockies team that went to the World Series, but they were swept by the Boston Red Sox. Affeldt signed a one-year deal with the Cincinnati Reds following the season, and he spent the entire year in the bullpen.
- Born: June 6, 1979 (age 40), Phoenix
- Spouse: Larissa Affeldt (1999-11-20 to present - Marriage)
- Aliases: Jeremy David Affeldt
- Height: 6′ 4″ (1.93m)