Illegally Batted Balls – Rules and Mechanics

The Rule

A major rule change, effective with the 2018-2019 rule book, was made with regard to the batter’s legal position in the batter’s box when she makes contact with the pitch: at the moment of bat-ball contact, the batter may not contact the pitch when any part of her foot is touching the ground outside the lines of the batter’s box. The previous rule stated: “…when her entire foot is touching the ground completely outside the lines of the batter’s box. Effective with the 2020-2021 rule book, the batter may not contact the pitch when any part of her body is touching the ground outside the lines of the batter’s box.

This is a big change and added another responsibility for the plate umpire. Changing the rule to “any part of her foot” and deleting the word “completely”, resulted in a lot of illegally batted balls being called at the beginning of the 2018 season. Although many slap hitters are adjusting to this, there are still instances, some of them obvious, for which this call is not being made.


There are no mechanics changes for the plate umpire for this updated rule. The plate umpire should give it the best effort to see this when it happens, but priority remains with tracking the pitch into the plate area. If the PU recognizes early enough that the batter is committed to swinging at the pitch, move the eyes to the batter’s feet (the base umpires will help with the checked swing). If the PU does not have a good look at the feet as the ball is contacted, do not call it. This is one of the calls for which an umpire must be 100% sure of the call. Otherwise, the mechanics stay the same – a very loud “dead ball” (at least two times) while coming into fair ground to get everybody’s attention.

In an effort to assist the plate umpire, two important changes have been made for base umpires:
• All umpires are jointly responsible for illegally batted balls
• When U3 is in the rotated starting position, he/she can be on either side of 2B. If U3 suspects the pitcher is violating the pitcher’s lane rule, U3 can move to the most appropriate position to get a clear view of this.

Please view the videos on illegally batted balls in the Video section of this Locker Room, and read the article U3 Starting Position When Rotated in the Mechanics section/Three-Umpire Specific.