The overturned call that gave Toronto the winning run in Sunday's 3-2 victory over the Twins stemmed from a 2014 rule change actually designed to protect catchers in collisions at home plate.
However, in providing protection for catchers, the rule also includes a list of things that they can and can't do. Whether Twins catcher Gary Sanchez adhered to the rules was the subject of Toronto's successful replay challenge of umpire Alan Porter's call.
Here's a look at the play:
The call stemmed from an increase in collisions at home plate, and is sometimes called the "Buster Posey rule" after a 2011 incident that resulted in a season-ending injury to the Giants' star catcher.
Let's go to the rule book:
The first part of the rule states:
"Unless the catcher is in possession of the ball, the catcher cannot block the pathway of the runner as he is attempting to score. If, in the judgment of the umpire, the catcher without possession of the ball blocks the pathway of the runner, the umpire shall call or signal the runner safe. Not withstanding the above, it shall not be considered a violation of this (rule) if the catcher blocks the pathway of the runner in a legitimate attempt to field the throw (e.g., in reaction to the direction, trajectory or the hop of the incoming throw, or in reaction to a throw that originates from a pitcher or drawn-in infielder). In addition, a catcher without possession of the ball shall not be adjudged to violate this (rule) if the runner could have avoided the collision with the catcher (or other player covering home plate) by sliding."
Baseball's rule book, as it frequently does in explaining complex rules, adds this comment: