He was discharged in time to play in the 1945 NFL season, signing with the Rams, the team which held his draft rights. Zirinsky played in five of the ten games played by the Rams during the 1945 season, a campaign which culminated with the team's 15-14 victory over the Washington Redskins in the 1945 NFL Championship Game. On the year he only carried the ball three times, gaining just three yards.