Balk Definition: First Baseman in Foul Territory During Pick-Off

Question
Is it a balk if the pitcher throws to first on a pick off when the first baseman has both feet in foul territory.

Answer
Mark,

All fielders (other then the catcher) must start play in fair territory.

If they do not start the play in fair territory, then the penalty is a balk.

If the first baseman is in fair territory, then moves into foul territory to catch the ball, then there is no penalty.

Hope this helps!

Brian