Official Baseball Rule 5.05(b)(2) states, "The batter becomes a runner and is entitled to first base without liability to be put out when—
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They are touched by a pitched ball which they are not attempting to hit unless (A) The ball is in the strike zone when it touches the batter, or (B) The batter makes no attempt to avoid being touched by the ball; If the ball is in the strike zone when it touches the batter, it shall be called a strike, whether or not the batter tries to avoid the ball. If the ball is outside the strike zone when it touches the batter, it shall be called a ball if they make no attempt to avoid being touched."
Accordingly, as leaning into a pitch most certainly doesn't meet the criteria for attempting to avoid it, Diaz was called back to bat.
Interestingly college posits a unique penalty for this violation that is different than OBR (and NHFS), per NCAA Rule 8-2-d-1a: "If the ball is in the strike zone when it touches the batter, or if the batter moves to intentionally get hit or freezes to allow a pitch that is not within the batter's box to hit them, the ball is dead, it shall be called a strike and the batter is not awarded first base."
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