In
baseball, being hit by a pitch refers to the
batter being hit in some part of the body by a pitch from the
pitcher. Per baseball official rule 6.08(b), a batter becomes a
baserunner and is awarded first base when he or his equipment (except for his bat) is touched by a pitched ball outside of the strike zone, and he attempts to avoid it (or had no opportunity to avoid it), and he did not swing at the pitch. The ball is dead, and other baserunners advance if they are forced to vacate their base by the batter taking first. Rule 5.09(a) further clarifies that a hit by pitch is also called when a pitch touches a batter's clothing.
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