Combined, Matt Bonner, Finley and Mason -- all starters -- shot 12-of-21 from 3-point territory.
"I think the night started with Tony Parker," Mason said. "Tony was able to share the ball early and the entire team was able to play unselfish basketball and take the open shot."
The Raptors have lost five straight for the second time this season to drop to 10-14. They are 2-10 in their last 12 games.
Toronto was 4-of-12 on 3-pointers. The Spurs also outrebounded Toronto 58-42 and finished with an 18-9 points-in-the-paint advantage.
"It's tough to beat a team like that," Raptors coach Jay Triano said. "We forced the ball to the perimeter and they made the shots. Pretty awesome display of shooting."
Jermaine O'Neal led the Raptors with 24 points despite a sore left shoulder. He was 12-of-20 from the floor and had 10 rebounds.
"I'm a little sore, but you just have to fight through it," said O'Neal, who played 15 minutes before getting hurt Friday night in a loss at Oklahoma City. "I expected this coming in."
Parker, 3-of-17 from the field Thursday night in the Spurs' loss in Orlando, hit a jumper just inside the 3-point line that gave the Spurs a 10-point lead with 6 minutes left in the third quarter.
"We had a very tough night against Orlando," Parker said, "so I was anxious to get back home and back on the court. I had trouble sleeping after that loss."
Toronto's Jose Calderon hit a 3-pointer and Joey Graham converted a 3-point play to make it 73-69 with 3:19 left in the third.
But the Spurs answered with their own 3-point plays. Duncan scored on a layup on an assist from Parker and made the free throw after the foul. And Bonner knocked down a 3-pointer, followed by a 20-footer from Parker, that gave San Antonio an 81-71 lead with 2:14 to go in the third.
"Those guys just really seemed to make a lot of 3s," O'Neal said. "Every time we would stop them it seemed like they would come back on the next possession with a 3.
"And [Parker] can turn those corners so quick and hurt you in so many ways. When we didn't score, they did, and it mostly was 3s."
Toronto made it a five-point game when Jason Kapono hit a 3-pointer with less than three minutes left in the game. But Duncan scored consecutive baskets to give the Spurs a 105-95 lead with 1:22 remaining.
"They rest him wisely, use him wisely, and when they need a bucket they know where to go," Triano said. "He's a guy that has delivered for them in the past for them and tonight he made tough buckets, too."
Spurs C Fabricio Oberto did not dress for the second straight game due to a sore left foot. Oberto has played 41 seconds the last four games. ... Toronto's Chris Bosh entered the game shooting 22-of-70 his last four games, and he started 1-for-7 Saturday night before ending with 6-of-14 shooting. ... The Spurs had to use a replacement public-address announcer after Kevin Brock was taken to a hospital when he injured both knees playing basketball at the arena before the game.