Kyle Lowry finished with 23 points five rebounds and five assists for Toronto. Serge Ibaka had with 26 points and four rebounds.
"The defensive effort was really good," head coach John Beilein said.
The Raptors took a 100-90 lead with 5:41 remaining. The Cavaliers scored nine straight points to cut the lead to one. Cleveland trailed 105-104 with 1:18 remaining, but the defending champions didn’t flinch in crunch time.
Norman Powell buried a 3-pointer to extend the Raptors' lead to four. A turnover by Kevin Porter Jr. led to a breakaway dunk Powell that put the game away.
Kevin Love led the Cavaliers with 23 points, five rebounds and four assists. He made six 3-pointers.
Collin Sexton finished with 23 points and four assists. The Cavaliers outrebounded the Raptors 52-37, but turned the ball over 21 times. Porter led Cleveland with seven giveaways.
"Forget the late turnovers, it was the early ones just as much the got in the way," Beilein said. "This is something that I do think we will control eventually. Experience and skill development and all these things make a difference."
Toronto finished with 14 turnovers.
The Cavaliers play the Warriors on Saturday at 8 p.m. at Rocket Mortgage Fieldhouse.