Randazzo called McCann out for illegal action, specifically for violation of Official Baseball Rule 6.03(a)(3): "A batter is out for illegal action when they interfere with the catcher’s fielding or throwing by stepping out of the batter’s box or making any other movement that hinders the catcher’s play at home base."
With a 1-1 count to McCann before Genesis Cabrera's changeup that resulted in a McCann swing-and-a-miss, the interference call put McCann out immediately (as soon as Toronto catcher Jansen was unable to throw the ball to second base) and returned runner R1 Cowser to first, as no bases may be run as a result of the dead ball caused by an interference call.
Note that this is not an example of unintentional backswing interference, because the proper outcome for that call would be a dead ball, runner returns to first, and a strike added to the count due to McCann's swing, which would make it a 1-2 count. With McCann out immediately, it is apparent that Randazzo's call was interference, not unintentional backswing contact (note: in high school, backswing is called follow-through and is treated as interference).
OBR 6.03(a)(3) and (4) Comment states, "If a batter strikes at a ball and misses and swings so hard they carry the bat all the way around and, in the umpire’s judgment, unintentionally hit the catcher or the ball in back of them on the backswing, it shall be called a strike only (not interference). The ball will be dead, however, and no runner shall advance on the play."
Video as follows:
Alternate Link: McCann called for batter interference, but did he interfere or did Jansen misstep?
Video as follows:
Alternate Link: McCann called for batter interference, but did he interfere or did Jansen misstep?
