Career
Simpson pitched for the Philadelphia Phillies Double-A affiliate, the Reading Phillies in 2007. Simpson has pitched in the majors for the Cincinnati Reds, Colorado Rockies, and Milwaukee Brewers of Major League Baseball. Simpson made his Major League debut on May 17, 2004.
He played for the Colorado Rockies in 2004 and 2005, Cincinnati Reds in 2005, and Milwaukee Brewers in 2006.
On July 7, 2008 Simpson signed a minor league contract with the Philadelphia Phillies. Simpson retired at the end of the season.