Kemba Walker led the way for the Celtics with 29 points and a dazzling defensive showing, but it simply wasn't enough as OG Anunoby drained a buzzer-beater for the Raptors win.
Jaylen Brown starred for Boston as well, notching his first career playoff double-double (19 points, 12 rebounds).
Jayson Tatum delivered down the stretch and finished with 15 points to go with nine rebounds.
On the Raptors' side, Kyle Lowry had a game-high 31 points. Fred VanVleet did his part as well contributing 25. And of course there was Anunoby, who had 12 points including the three most important points of the contest.
FINAL SCORE: Toronto Raptors 104, Boston Celtics 103
SERIES: 2-1 Celtics
Kemba picks up where he left off
Tatum from deep
Tatum --> Theis
Kemba beats the halftime buzzer
TIME LORD SLAM
Kemba on fire
Tatum ties it
Brown throws down the hammer
Anunoby beats the buzzer
The C's will look to take a 3-1 series lead Saturday night with tip-off set for 6:30 p.m. Celtics Pregame Live begins at 5:30 p.m. right here on NBC Sports Boston.