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John Popovich (March 6, 1918 – February 3, 2004) was an American football player and coach. He played in the National Football League (NFL) from 1944 to 1945, for the Pittsburgh Steelers and "Card-Pitt", a team that was the result of a temporary merger between the Chicago Cardinals and the Steelers. The merger was result of the manning shortages experienced league-wide due to World War II. Popovich was signed to "Card-Pitt" midway through the season, after he returned from the Army due to a medical discharge. Popovich served as the head football coach at Waynesburg College—now known as Waynesburg University—in Waynesburg, Pennsylvania from 1955 to 1958, compiling a record of 12–16–4.
Forr, James (2003). "Card-Pitt: The Carpits" (PDF). Coffin Corner. Vol. 25, no. 3. pp. 1–8. Archived from the original (PDF) on October 22, 2012 – via Professional Football Researchers Association.