DURHAM—Warren Long ran 55 yards for a touchdown and recovered a fumbled punt return late to help No. 23 Northwestern beat Duke 19-10 on Saturday.Solomon Vault returned the opening kickoff of the second half 98 yards for the touchdown that put the Wildcats (3-0) ahead to stay.NU forced three turnovers and opened a season with three victories for the first time since 2013 – also the last time the Wildcats were ranked.Thomas Sirk had a 5-yard touchdown run for Duke (2-1), which trailed 12-10 early in the fourth quarter but forced Northwestern into a third-and-1 at its own 45.Long took a handoff, burst untouched through the line and sprinted to the end zone to put the Wildcats up by nine with 12:31 remaining.Duke failed to cross midfield on its next two possessions, but forced a punt with about six minutes remaining. Ryan Smith called for a fair catch at midfield but the ball bounced off his pads and Long pounced on it at the Duke 49.The Blue Devils finished with 327 total yards to 271 for Northwestern, but had just 152 in the second half.Sirk finished 24 of 39 for 150 yards with an interception for Duke.Ross Martin kicked a 38-yard field goal for the Blue Devils, while Jack Mitchell had field goals of 37 and 44 yards for the Wildcats.Clayton Thorson was 9 of 23 for 70 yards in his first road start with two interceptions for Northwestern.The Wildcats took control of this game late in the first half by forcing two turnovers. A third – Dean Lowry’s scoop-and-score of a deflected screen pass – was overturned after a review determined it was a forward pass.Vault then gave the Wildcats the lead with his big return, though Kyler Brown kept it 9-7 by blocking the extra point.And Northwestern went up by five on Mitchell’s long field goal on its next possession before Martin pulled Duke back within two with his kick on the second play of the fourth quarter.The Wildcats entered having allowed a total of two field goals all season, but gave up their first touchdown on Duke’s second possession: Sirk’s scoring run came five plays after DeVon Edwards brought an interception back to the NU 26.The teams then combined for 11 straight punts before the Wildcats started forcing turnovers, turning one – Shaun Wilson’s fumble at the Duke 40 – into Mitchell’s shorter field goal with 1:23 left that made it 7-3.