So Sullim...A DB 'catches a pass' thrown by the opposing qb...and as often occurs backtracks while running.Lets say he runs backward at a slight angle halfway across the field...then slips and the ball falls(knee on ground) out of his hands before he is touched by someone from the offensive team. All of this could take from..oh 4-8 seconds.
Then by your definition he is still in the act of catching the ball because he has not moved forward.--after having had the ball for quite a while. ??? come on.