Justin Francis Klemm
- Height 6' 3", Weight 210 lb.
- School Indiana Wesleyan University
Justin Klemm was a major league umpire for parts of four seasons, from 2000 to 2003, officiating in 186 games as a fill-in umpire. He spent nine seasons as a professional umpire, including four years in the International League. He also worked in the Arizona Fall League and worked in Major League Baseball-sponsored umpiring clinics in China and Australia.
In 2004, he retired from officiating to join Minor League Baseball's Professional Baseball Umpire Corporation as a field evaluator and instructor, working on the training and professional development of minor league umpires, as well as heading an evaluation staff consisting of six persons. In 2008, he became executive director of the corporation.
On February 13, 2014, he was appointed Director of instant replay by Major League Baseball, to oversee the implementation of the new rules pertaining to instant replay adopted in the 2013-14 off-season. Six new umpires were added to the major league umpiring staff at the same time to provide additional staff available to review tapes from the MLB Advanced Media headquarters in New York, NY. A 7th new umpire was hired to replaced the late Wally Bell, who had passed away in the off-season.