SACRAMENTO, Calif. — Brock Purdy and the San Francisco 49ers were on the brink, needing a spark to overcome a big deficit and avoid a third straight loss in the conference title game. Brandon Aiyuk delivered with an improbable catch that helped save San Francisco's season. Purdy's 51-yard pass that deflected off a defender's facemask into Aiyuk's hands helped the Niners rally from 17 points down at halftime to beat the Detroit Lions 34-31 on Sunday and reach the Super Bowl.