"It's a process," Casey said. "I can see us growing and getting better from this second half."
After scoring 62 points in his previous two games, Mayo shot 8 for 17. Carter scored 17 points against his former club and Darren Collison chipped in 15.
Kaman, who missed the first two games of the season with a strained right calf, started in place of Brand and played 33 minutes. Mavericks rookie Jae Crowder made his first career start in place of Marion, who is expected to miss three games.
"I anticipated playing a little more with Elton out," said Kaman, who also grabbed eight rebounds. "I didn't know it would be so much. I'm definitely not in the shape I was in before I got injured."
The Mavericks led 61-50 and pushed their advantage to 15 points midway through the third quarter behind Mayo's seven points.
The Raptors outscored the Mavericks 12-5 the rest of the period to get within 82-74, the closest they'd been since the first quarter.
Toronto's Amir Johnson had 18 points and 11 rebounds off the bench, and Alan Anderson scored 13.
Kaman scored eight points in the first quarter as the Mavericks jumped out to a 36-24 lead after the first quarter.
The Mavericks stretched their lead to 42-26 early in the second before the Raptors rallied. Bargnani scored five points in an 11-4 run that brought Toronto within nine.
NOTES: Casey was an assistant with the Mavericks from 2008-11. ... Dallas television announcer Mark Followill returned after missing two games while recovering from a bicycle accident. .. Bargnani played in his 403rd game, tying Carter for fifth place on the Raptors' career list. ... The Mavericks are 28-22 without Nowitzki.