KANSAS CITY, Mo. — The New England Patriots are headed to their third straight Super Bowl, once more thanks to Tom Brady’s brilliance. The five-time NFL champion guided the Patriots 75 yards after winning the overtime coin toss, and backup Rex Burkhead’s 2-yard TD lifted New England past Kansas City 37-31 for the AFC championship Sunday night. The drive, during which New England (13-5) had three third-down conversions, against an exhausted defense was reminiscent of when the Patriots beat Atlanta in the only Super Bowl to go to OT two years ago. “Overtime, on the road against a great team,” Brady said.