BOULDER, Colo. — Cody Hagen scored on a 32-yard run early in the fourth quarter and Bear Bachmeier threw two touchdown passes, helping No. 25 BYU rally from an early deficit to beat Colorado 24-21 on Saturday night.Cougars linebacker Isaiah Glasker sealed the win by intercepting Kaidon Salter’s pass with 50 seconds remaining.Bachmeier was 19 of 27 for 179 yards and connected with Chase Roberts for two short TD passes. The freshman QB also rushed for 98 yards as the Cougars (4-0, 1-0 Big 12) started 4-0 for a second straight season. “He did a great job,” BYU coach Kalani Sitake said of Bachmeier. “Didn’t ever look like he was frazzled or that he was shell-shocked at all. He came like that. Credit his family and the way he was raised. He was a cool customer and I loved the way he was leading out there.”The Cougars, who trailed 14-0 midway through the first quarter, took the lead for good on an end-around play that befuddled the Buffaloes. Bachmeier faked an inside handoff before flipping the ball to Hagen, who sprinted into the backfield from his receiver spot. He was hardly touched and followed a convoy to the end zone with 14:02 remaining.The Buffaloes (2-3, 0-2) had something goin …