According to Malika Andrews of ESPN and Gary Washburn of the Boston Globe, Smart could be heard loudly yelling profanities from the locker room:
After going off for 26 points in Game 1, shooting 6-of-13 from three, Smart had a more subdued 14 points and four assists on Thursday. He shot 5-of-13 from the field and 2-of-6 from three, finishing -3 on the night.
It's perhaps a concern for Boston that Smart took more shots than Jayson Tatum (6-of-12 from the field) and nearly as many as Jaylen Brown (8-of-14). Kemba Walker led the team with 19 shots, also leading the team with 23 points.
It's unclear what precisely led to the blowup, though after falling into a 2-0 hole in the Eastern Conference Finals, the pressure is beginning to mount for Boston.