1972 – The major leagues make modifications to the official save rule, a statistic officially adopted before the 1969 season. A pitcher shall be credited with a save if, when entering a game as a reliever, he finds the tying or winning run on base or at the plate, and he preserves the lead. Or he pitches three effective innings and preserves the lead. The rule will be tweaked again, to take its lasting form, before the 1975 season.