Upton Bellenfant drilled a 37-yard field goal in overtime as visiting Buffalo upset No. 23 Northern Illinois 23-20 on Saturday afternoon in DeKalb, Ill.Buffalo improved to 2-16 all-time against ranked opponents. It is the Bulls’ first win over a ranked foe since 2008. Buffalo cornerback Marquis Cooper blocked a 42-yard Kannon Woodill field-goal attempt on the Huskies’ overtime possession.Linebacker Shaun Dolac had a career-high 19 tackles, 4.5 tackles for a loss and an interception to lead Buffalo’s defense.Buffalo trailed 14-3 at halftime, but Dolac returned his interception to the NIU 20 with 5:39 left in the fourth quarter. That set up Bellenfant’s 43-yard field goal and gave the Bulls their first lead at 20-17. Dolac entered the game with the most tackles in the MAC this season and tied for the national lead at 14.3 per game.Northern Illinois drove 66 yards in 13 plays and Woodill tied the game 20-20 on a 27-yard field goal with 24 seconds left in regulation.Huskies quarterback Ethan Hampton entered the game as the national leader in passing efficiency and passing yards per attempt. Yet, the Buffalo defense held Hampton to 23-for-43 for 194 yards and an interception.C.J. Ogbonna was 10-for-17 for 107 yards and a touchdown for Buffalo.Antario Brown had 73 rushing yards and two touchdowns on 24 carries for Northern Illinois. Brown’s 5-yard touchdown run gave Northern Illinois a 7-0 first-quarter lead.