Balk?

[Kyle Flanagan]

Can there be a balk with no batter in the box?   For example, a runner on first and the pitcher is engaged on the rubber and commits a balk ( drops the ball, starts and stops a delivery....) but the next batter is leaving the on deck circle and is on his way to the plate.  

[Stk004]

Yes. Balks have nothing to do with whether or not the batter is in the box. Sounds like the pitcher should probably wait to get on the rubber until the batter is near home plate. 

[Senor Azul]

OBR (Definitions) A BATTER is an offensive player who takes his position in the batter’s box.

OBR Official Interpretation:  2018 Minor League Baseball Umpire Manual: A batter’s time at bat begins the moment the preceding batter is put out or becomes a runner.

From the 2016 BRD (section 52, p. 56): 

Note 70:  The definition affects balks at all levels. Question:  Can a pitcher balk when a batter is not in the box? Answer: Yes.

For NCAA their current rule 9-4a-5 actually states “…a player becomes the batter as soon as the previous batter reaches base, or is put out. The new batter does not have to enter the batter’s box to be considered the batter.”

[noumpere]

4 hours ago, Kyle Flanagan said:

Can there be a balk with no batter in the box?   For example, a runner on first and the pitcher is engaged on the rubber and commits a balk ( drops the ball, starts and stops a delivery....) but the next batter is leaving the on deck circle and is on his way to the plate.  

You can remember this by noting that balks have to do with illegally deceiving a runner and have nothing to do with the batter.