In the opening game of a season freighted with expectation and rivalry, New England Patriots receiver A.J. Brown — acquired as a symbol of the franchise's renewed ambitions — left Lumen Field in Seattle with an ankle injury before the night was finished. His departure in the third quarter of a rematch against the reigning Super Bowl champions distilled one of sport's oldest truths: that the grandest intentions are always subject to the fragility of the human body. The Patriots held a 10-3 lead entering the fourth quarter, but the larger question — how long their star receiver would be absent —