Jonathan Paul Martinez
- Bats Right, Throws Right
- Height 6' 2", Weight 205 lb.
- School University of New Orleans, Louisiana State University
- High School Isidore Newman High School
J.P. Martinez was a minor league pitcher, spending 2004-2007 in the Minnesota Twins chain (reaching AAA briefly). He was taken by the Baltimore Orioles in the AA portion of the 2007 Rule V Draft and ended his career in 2008. Over his five minor league seasons, Martinez had a 17-14 record with a 3.36 ERA and 40 saves. His brother-in-law Joe Pietro also played pro ball.
Following his playing career, Martinez worked on a master's degree in architecture at Louisiana State University. He also began his coaching career at the high school level before moving to the professional coaching ranks in 2015.
- 2012 Assistant coach Isidore Newman High School
- 2013-2014 Head coach Pope John Paul II Catholic High School  
- 2014 Pitching coach St. Cloud Rox
- 2015 Pitching coach GCL Twins
- 2016-2017 Pitching coach Cedar Rapids Kernels
- 2018-2020 Minor league assistant pitching coordinator Minnesota Twins
- 2021 Assistant pitching coach San Francisco Giants