The link below is a good explanation on this subject by the VP of officiating for the Louis Murphy TD call in 2009.
What caught my attention was how he focused on one key point...
AFTER the player makes contact with the ground possession must be maintained.
To me Calvin clearly was going to the ground and did not maintain control after he touched the ground. Pretty cut and dry when considering how the rule is written:
Item 1: Player Going to the Ground. If a player goes to the ground in the act of
catching a pass (with or without contact by an opponent), he must maintain control
of the ball after he touches the ground, whether in the field of play or the end zone. If
he loses control of the ball, and the ball touches the ground before he regains control,
the pass is incomplete. If he regains control prior to the ball touching the ground,
the pass is complete.
Link:
http://www.freep.com/article/20100913/BLOG...Johnson-s-catch