The AP reports: Leon Powe scored 17 points in the second half, including the go-ahead basket with just over two minutes left, to lead the Boston Celtics to a 90-86 win over the Cleveland Cavaliers in a preseason game Tuesday night. Powe’s dunk with 2 minutes, 17 seconds remaining put the Celtics ahead 85-84. Boston trailed 81-74 following an 8-0 Cleveland run early in the fourth quarter… Ray Allen had 15 points in 23 minutes for the Celtics (3-1). Paul Pierce added 14 points and Kevin Garnett had 11 points and seven rebounds. Each of Boston’s “Big Three” left the game for good midway through the third quarter. Daniel Gibson led Cleveland with 14 points. LeBron James had 12 points, three rebounds and two assists in 18 minutes. Jawad Williams added 13 points and Zydrunas Ilgauskas had six rebounds.