Al Horford hit a huge 3-pointer against his former team and the Boston Celtics broke open a tight game in the closing minutes to beat the Atlanta Hawks 128-120. The Celtics win the opening-round playoff series four games to two and advance to face the Philadelphia 76ers. Game 1 is Monday night in Boston. The Celtics ripped off an 11-0 run that included three straight 3-pointers. Horford’s big shot was sandwiched around treys from Jayson Tatum and Jaylen Brown. Brown led the Celtics with 32 points, while Tatum had 30. Trae Young paced Atlanta with 30 points but made only one field goal in the second half.