Born to a Polish mother and Italian father, both of whom are immigrants, Rienzi, was a first generation American citizen. He grew up to play for Xavier High School in Manhattan, NY, and later proceeded to play with St. Joseph’s College Brooklyn (D3), where he became the all time appearances leader for pitchers, with forty-five appearances. Rienzi was a member of the Polish National Baseball Team from 2015-2019, competing in various competitions both in the U.S and Europe. Joined the coaching staff at St. Joseph’s College starting summer 2021, serving as an assistant and working primarily with catchers.