The dunk came in the fourth quarter of the Celtics' 105-87 victory on Tuesday at TD Garden in Boston.
The Celtics led 92-79 with about 6:40 remaining in the season-opening clash. Celtics guard Kyrie Irving ran down the middle of the floor before spotting Brown lingering down the right flank. He fired a chest pass to Brown, who took one dribble before elevating inside of the 3-point line.
Brown held the ball as he eyed the 7-foot Sixers center. Embiid prepared to pounce before leaving his feet and meeting Brown above the paint. But the Celtics star still managed the crank the ball back in his right arm and slam the ball through Embiid's block attempt. Embiid fell to the floor after the aerial contact.
Brown had 12 points, five rebounds and two assists in the victory. Jayson Tatum led the Celtics with 23 points. Tatum also had nine rebounds, three assists and a steal. Embiid led the Sicers with 23 points and 10 rebounds in the loss.
The Celtics face the Raptors at 8 p.m. on Friday in Toronto. The Sixers host the Chicago Bulls at 8 p.m. on Thursday in Philadelphia.