Mendoza line. The figurative boundary in the batting averages between those batters hitting above and below .215. It is named for shortstop Mario Mendoza whose career (1974-1982) batting average for the Pirates, Mariners and Rangers was .215. The figurative boundary in the batting averages between those batters hitting above and below .200. “When a struggling hitter pulls his average above .200, he has crossed the Mendoza Line.” (Sports Illustrated, Sept.