I think it was a catch, but not a touchdown. He had full control when his knee hit the ground. Ball on the 1-yard line.
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But NO DEFENDER had touched him before he scored.
TD
It’s not a catch until he completes the catch. If he’s going to the ground, that includes the player hitting the ground and maintaining control for a few moments afterwards.
He’s not down until he is touched while on the ground or on the ground after being touched on his way to the ground.
That was my opinion, too. Too many times the dummies lose all situational awareness and snatch defeat from the jaws of victory instead of just hugging the ball and wait for the whistle.