If your out when the ball crosses the boundary, how can you make a tip toe catch with the ball out of bounds? Honest question
RULE 3 DEFINITIONS
SECTION 20 OUT OF BOUNDS, INBOUNDS, AND INBOUNDS SPOT
ARTICLE 4 OUT OF BOUNDS SPOT
Item 1. Loose Ball. If a loose ball touches anything on or outside a boundary line, the out of bounds spot is the forward point of
the ball when the ball crosses the sideline.
Item 2. Runner Out of Bounds. If the ball is in player possession when that player goes out of bounds, the out of bounds spot is
the forward point of the ball when the ball crosses the sideline, or, if the ball does not cross the sideline, the forward point of the
ball at the instant the player is out of bounds.
Item 3. Runner Inbounds. If the ball, while in possession of a player who is inbounds, is declared out of bounds because of
touching anything that is out of bounds, the out of bounds spot is the yard line through the forward point of the ball at the instant
of such touching.
Since Kupp was a runner at that point, the ball is marked where it crosses the sideline. If he caught the ball on the sideline, with the ball snatched on the other side of the sideline, if he leans the ball forward as he comes down out of bounds, he would get the spot he leaned for as soon as he lands out of bounds.