The Raptors rank 25th in the NBA in three-point % (31.9%), and the Celtics rank 16th in three-point % allowed (35.4%). The offense needs to find something against an average defense.
League average is 34.7%, so the Raptors are 2.8 points below it. Scottie Barnes leads them with 23.5 points a game on 52.2% true shooting.