The baseball rule book defines a tag as:
A TAG is the action of a fielder in touching a base with his body while holding the
ball securely and firmly in his hand or glove; or touching a runner with the ball, or with his
hand or glove holding the ball, while holding the ball securely and firmly in his hand or
Nothing about maintaining possession through hitting the ground. This is an absolute non-issue being made into an issue by ESPN. I just heard Dave Campbell go on the radio and actually say that the call was wrong...mind you, he didn't defend it. He just said it was wrong.
He is tagged, when the ball is alive, while off his base.
Discussion over. That took me 3 minutes. Tag-gate is going to go on for weeks.