BOSTON, Nov. 23 (Ticker) -- In Vince Carter, the Toronto Raptors have one of the best offensive players in the NBA. But they turned to an unlikely scorer to lead a fourth-quarter rally.

Antonio Davis was consistent, scoring four points in each quarter.

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Reserve Keon Clark scored 12 of his season-high 19 points in the final quarter as the Raptors scored 15 of the final 19 points en route to a 91-89 victory over the struggling Boston Celtics.

Toronto leans on the firepower of Carter nearly every game, but superstar was held to 18 points on 6-of-21 shooting. Without his production, the Raptors found themselves behind until Clark sparked a comeback.

Toronto trailed, 85-76, with 6:58 remaining when Clark made consecutive dunks to spark a 13-0 run. Antonio Davis gave the Raptors the lead for good with a fadeaway jumper with 2:24 remaining and Alvin Williams capped the run with a pull-up jumper at the 1:44 mark.

Clark added a free throw before Boston's Antoine Walker scored on a follow shot to make it 89-87 with 52 seconds left.

"Every win is good, but when you're down and it looks like things aren't going your way and we turn it around, it's always something to build on," Clark said.

After Carter made 1-of-2 free throws, Paul Pierce and Kenny Anderson missed potential game-tying 3-pointers. Clark grabbed the rebound off Anderson's miss and sealed the game on a free throw with seven seconds remaining.

Clark made 7-of-10 shots in 19 minutes, adding nine rebounds and two blocks.

"Tonight was my night so I'm just glad I could help out and get us a victory," he said. "My teammates were looking for me, they were calling me to the ball and whenever you get confidence from the guy with the ball it's going to give you confidence as well. If they want me to shoot I'm going to shoot. I know I can, they know I can, so I took advantage of the situation.

"Keon gave us a great lift," Toronto coach Lenny Wilkens said. "He came in with some great energy. He blocked some shots, he rebounded, he scored and when we got him on the low block he was able to get to the basket. I thought he played terrific; it was one of his better games."

Davis finished with 16 points and eight rebounds and Williams scored 13 points for Toronto, which snapped a two-game losing streak and has won its last three on the road.

Walker had 25 points and 12 rebounds and Pierce added 24 and eight, but the duo combined to score just 12 points in the fourth quarter.

"It's a lack of focus and a lack of concentration towards the end," Pierce said. "We think we can do it all by ourselves, but this is a team effort. We didn't execute the way we wanted to, we took bad shots, we turned the ball over and those things are going to hurt you, especially late in the game."

Boston scored just four points in the final 6:58 and shot 39 percent (32-of-86) en route to its third straight loss. The Celtics made 9-of-23 3-pointers.

"We usually have good fourth quarters and we just had a bad fourth quarter," Walker said. "We let a golden opportunity slip away from us."

Boston took the lead in the first quarter and did not trail until the final minutes.

The Celtics went on a 10-2 run midway through the second quarter to take a 41-29 lead with 5:49 left. They had a 48-39 lead at halftime as Erick Strickland scored all 13 of his points.

Boston opened the second half on a 14-8 spurt to build its largest lead, 62-47, with 7:48 to go. Rookie Joe Johnson scored the first six points and Pierce added the final five, capping it with a three-point play.

Toronto responded by scoring the next 12 points to climb within 62-59 with 4:20 left and remained within single digits until the fourth. Carter scored four points in the burst while Williams and Morris Peterson added 3-pointers.

The Raptors shot just 43 percent (36-of-84), made 4-of-17 3-pointers and only 15-of-24 free throws, but were still able to defeat Boston for the eighth time in 12 meetings.

"A win is a win, I don't care how we got it," Carter said. "They could have accidentally given us a point. Game over, I'll take it. That's how bad we needed a win, I don't care how bad we played throughout the game. The thing we can learn from is that we were able to come back and find a way to win."

"We played a tough game last night (vs. Milwaukee) and we proved it's mental," Wilkens said. "Sure our bodies are a little fatigued, but that means that you've got to play smart and I thought in the second half we did. That's the way we have to play every game."