Illegal hit

Question
In a coed game recently, the opposing batter hit a fair ball, but his hitting stride took his front foot out of the batter's box.  I protested to no avail as the umpire ruled that there was no batter's box.  The chalk lines had been rubbed out during the course of the game.  I said it was obvious because his foot came down on the third base line.  The umpire ruled that it was not an infraction to have one or both feet in fair territory when striking the ball.  I disagree.  What do you say.

Answer
Hi Michael,

The batter's box is 3' wide by 7' long.  Any part of the foot touching any part of the line is considered in the box, which widens and extends the box quite a bit.

The foot can be in the air when contact is made (so it's not necessarily important where the foot comes down). Only if the foot is on the ground completely outside the line (or in contact with the plate) when the ball contacts the bat do we have an out of the box call.

It is a judgement call by the umpire.

Mark