That's why I said "legally" blocked. The point was that players of either team may block opponents even if the block is well remote from the ball carrier. They don't have to be attempting to get to the ball carrier (defense) or directly blocking for the BC (offense), as long as they make a block that is otherwise legal. A player could be 40 yards behind the play, and throw a block on an opponent, while the ball is alive, from the front, above the waist, below the neck, with no grasping or clamping involved, and with the opponent fully aware of the impending block, and the block would be legal, by rule. The player being blocked, and his coaching staff, probably won't like it. It will probably require some action on our part to separate them before it escalates into an altercation. But, until that point, there is no flag to be thrown.
Robert