<P> A mercy rule, slaughter rule, knockout rule, or skunk rule ends a two - competitor sports contest earlier than the scheduled endpoint if one competitor has a very large and presumably insurmountable lead over the other . It is called the mercy rule because it spares further humiliation for the loser . It is common in youth sports in North America, where running up the score is considered unsporting . It is especially common in baseball and softball in which there is no game clock and a dominant team could in theory continue an inning . </P> <P> The rules vary widely, depending on the level of competition, but nearly all youth leagues and high school sports associations and many college sports associations have mercy rules for sports including baseball, softball, American football and association football . </P>

Is there a run rule in the mlb