Casey was incensed that the Cavs were called for only 10 fouls in the game. He repeatedly referenced what he believed were non-calls for contact on Biyombo, who set a team record with 26 rebounds and had four blocks.
"[Biyombo] is not getting the calls," Casey said. "We shoot zero free throws in the fourth quarter. Zero. He's getting hit. There's one play where they almost have a brawl. He gets killed on that play.
"I don't know if he's getting hit because of how physical and tough he is, but he's getting cracked. To his credit, I thought he was going to lose his head when he got the technical foul, but he kept playing.
"He's one of the top rebounders in the league, and no telling how many times he gets hit and fouled under there without being called. Again, I'm going to say this: I think he gets hit almost on every rebound and putback there is, and he just doesn't get the calls, whether he's rolling to the bucket, and we've just got to have consistency with that."
Casey was asked about other aspects of the victory, which snapped the Cavs' 10-game winning streak to start to the postseason. But he kept bringing the discussion back to the non-calls on Biyombo.
The Raptors coach was also upset about a minor confrontation in the first half, when DeMarre Carroll was assessed a technical foul after Tristan Thompson accidentally elbowed LeBron James. Thompson also received a technical on the play.
The Cavs took 16 free throws to the Raptors' 13 on Saturday and have taken 35 more free throws over the first three games of the series.
"I've been on both sides of it," said Casey, whose most recent fine for public criticism of officials came three years ago. "I've been where the whistle has been in favor of you. But for whatever reason -- and I understand we have great officials and it's a hard game to call -- but some of these fouls are unbelievable."
Jones, a veteran signed by the Cavs in April who has a reputation for chippy play, hit Biyombo in the groin area after he entered with 90 seconds left in the game.
"Whenever the league has a chance, they probably want to take a look at that," Biyombo said of the play. "That's all I can say on that."
Biyombo, who has committed several hard fouls on James in this series, was called for a flagrant foul for grabbing James around the neck a few moments earlier.
James, who earlier in the series referenced opponents' getting away with hard fouls on him, quoted Jay Z's "Streets Is Watching" to explain why he tries to take the high road.
"I always think back to the Jay Z phrase and a line he had: 'If I shoot you, then I'm brainless. If you shoot me, you're famous.' What am I to do?" James said. "That always plays in my head. Every time I feel like I want to react, I've got to keep my brain."