You’ve probably heard of the “Mendoza Line”. It’s a classic baseball expression that sets a batting average of .200 as the arbitrary marker for a player who can’t hit. The origins of the phrase are somewhat murky, but most agree it began in the 1979 season, when Seattle Mariners SS Mario Mendoza was floating under a .200 batting average, and his teammates were ribbing him about it.
Mendoza wasn’t an awful player, especially when he could field his position well and SS demands were mostly for slick glove rather than big slugging in that era. That’s good, because in this era not many players, no matter their defensive prowess, would be able to last the 8 seasons Mendoza did with his career 38 wRC+.