Norman Powell scored a season-high 14 points, and the Raptors won their fourth straight at home.
Leonard made all seven of his field-goal attempts in the third quarter and added five foul shots. His 19 points were the second most in any quarter by a Raptors player this season. Serge Ibaka scored 20 points in the first quarter of a Nov. 4 road win against the Los Angeles Lakers.
Leonard shot 16 for 22 overall, missing all three attempts from 3-point range. He went 13 for 17 at the free-throw line.
After making two 3-pointers in the first half, the Raptors connected on their first three long-range shots of the third quarter, turning a two-point halftime deficit into a 12-point edge midway through the quarter. Siakam went 3 for 3 from 3-point range in the third and scored 13 points. Toronto outscored Utah 44-32 to take a 95-85 lead into the fourth.
Toronto guard Kyle Lowry sat for the eighth time in nine games because of a sore lower back. Before the game, the Raptors said Lowry had travelled to New York last Friday to receive anti-inflammatory injections.
Rubio started after sitting out Saturday’s win over New York because of a sore left knee and sore lower back, while Crowder was back after missing the victory over the Knicks because of a sore left thumb.
Leonard scored 10 points in the first quarter, and all five Raptors starters made at least one basket as Toronto led 26-24 after one.