ORCHARD PARK, N.Y. — The defining play may have come from the right paw of Mario Williams, Buffalo’s 6-foot-6 Pro Bowl defensive end. Yet no member of a self-effacing and dominant Bills defense is willing to consider the idea that the team’s upset of the Green Bay Packers on Sunday was a single-handed achievement.

With less than two minutes left in the game, and Buffalo clinging to a 6-point lead, Packers quarterback Aaron Rodgers took a snap from center at the Green Bay 10-yard line and dropped back to pass. Williams muscled past right tackle J C Tretter, employing his long reach to swat the ball free.

Rodgers searched frantically, like a parent who has lost sight of a toddler. By the time running back Eddie Lacy scooped up the loose ball in the end zone, the Bills had a safety, en route to a surprising 21-13 victory that dropped the Packers to 10-4.