Before a single regular-season snap has been taken, the Atlanta Falcons find themselves navigating the oldest uncertainty in professional football: the fragility of the quarterback position. Tua Tagovailoa, the signal-caller brought in to anchor Atlanta's offense, will not take the field Sunday against the Pittsburgh Steelers, leaving Cooper Rush to carry the weight of an opening day that was supposed to look very different. It is a reminder that the plans teams build through long offseasons can unravel quietly in the days before the season even begins.