John Clarence "Nap" Kloza (September 7, 1903 – June 11, 1962) was a professional baseball player and manager. Listed at 5' 11", 180 lb., he batted and threw right-handed. Sometimes he is credited as Jack Kloza. Kloza was hailed as a potential Babe Ruth at that time, but his major league experience was cut short by illness, from which he never fully recovered his best playing strength, appearing in parts of two seasons. He was a .150 hitter in 22 games, driving in two runs and scoring five more without home runs.