Halftime: Virginia 25, Duke 21 CHARLOTTESVILLE, Va.—Duke struggled through its lowest-scoring first half of the season—no surprise against Virginia's top scoring defense in the nation—but the Blue Devils have responded with a strong defensive effort of their own to stay in the game.After a slow start with just two points in the first six minutes, a 10-0 run got No. 12 Duke back into it. However, it still trails No. 14 Virginia 25-21 at John Paul Jones Arena due to a field-goal drought of 8:20 to finish the half. The Blue Devils are shooting just 33.3 percent from the field, but have held the Cavaliers to just 32.1 percent shooting in the slow-paced defensive struggle.Virginia built an early seven-point lead, as Duke turned the ball over three times early and missed its first four 3-point attempts, but quick triples from Kennard and Allen brought the Blue Devils back within one, and a hook shot from Harry Giles in the paint put them in front for the first time eight minutes into the game.Graduate student Amile Jefferson converted a driving layup midway through the half to cap Duke's run, but a corner triple from Virginia point guard London Perrantes on the ensuing possession ended a scoring drought of almost six minutes for the home team and tied the score.The Cavaliers went on to attack the basket effectively after Jefferson had to go to the bench with two fouls, getting to the rim for two quick layups to trade baskets with the Blue Devils, and 12 of their 25 points have come inside the paint.Jefferson was whistled for his third foul with 3:18 left in the half on a moving screen, as head coach Mike Krzyzewski's decision to put him back in the game quickly backfired.Duke had a chance to extend its three-point lead late in the half but squandered a few chances, then a 3-pointer from freshman Ty Jerome tied the game at 21 with 1:57 left and sent the home crowd into a frenzy. Two free throws from Perrantes put the Cavaliers back in front, and a few more stops and a second-chance layup from Marial Shayok gave them all the momentum heading into the locker room.Here are some observations from the first half:Matt Jones kept Perrantes in check to start the half, but the Virginia point guard did his damage while being guarded by Luke Kennard and Frank Jackson. Perrantes and Jayson Tatum lead all scorers with seven points.Duke has done well when it is making the extra pass to try to keep the Cavaliers from having time to rotate and recover on defense. Four different Blue Devils have an assist on just seven made field goals.Cavalier center Jack Salt scored four points in the first four minutes, the most he has scored in a game since Jan. 21. Salt picked up two early fouls, though, and had to sit for much of the half.Jefferson's foul trouble has forced Giles into more action already than he has seen in an entire game since Jan. 28, and the freshman big man has notched four points on 2-of-2 shooting. Giles and Tatum have shown their inexperience too, though, with five of the team's eight turnovers.