Kevin Garnett led the Celtics with 20 points and 13 rebounds, Rajon Rondo had 18 points and 14 assists and reserve Jason Terry had 16 points. Bass finished with 11.
Bradley Beal, Kevin Seraphin and Martell Webster each scored 16 points for the Wizards (0-3).
Bass hit a tiebreaking free throw, making it 93-92, then scored on a twisting layup on the next possession. He added a breakaway dunk with 37.7 seconds left to help seal it.
Boston (2-2) beat the Wizards 89-86 in Washington on Saturday night.
Source: Associated Press