Knapp was hired by the Tigers in 2008 to replace Chuck Hernandez. He was relieved of his duties with the Detroit Tigers on July 3, 2011.
Knapp was named minor league pitching coordinator by the Kansas City Royals on September 28, 2011.[3]
He joined the Los Angeles Dodgers organization for the 2013 season as their assistant minor league pitching coordinator.[4] He was promoted to full minor league pitching coordinator in 2015.[5] At the conclusion of the 2016 season he left the Dodgers to assume a new post as International Pitching Coordinator for Major League Baseball.
In 2018, Knapp returned to coaching as the pitching coach for the Durham Bulls, the AAA affiliate of the Tampa Bay Rays.[6] The Rays promoted Knapp to assistant pitching coach on their major league roster for the 2022 season.[7]