BLACKSBURG, Va. — Virginia Tech head coach Buzz Williams has been known to change dress shirts during halftime of games because of his propensity to sweat during a game, but for the first time this season he switched into a sweater. The custom-made garment worked as the Hokies won a game decided by three points or fewer for just the third time this season — out of 10 attempts. Malik Muller hit a 3-pointer with 18 seconds left and finished with 17 points to lift Virginia Tech to a 65-63 victory over Georgia Tech on Monday.