PHOENIX -- The Phoenix Suns' reserves kept the game interesting, but the Toronto Raptors' starting lineup showcased too much firepower.

DeMar DeRozan scored 18 of his 37 points in the third quarter, and Toronto's starters totaled 99 points in a 115-109 win over the Suns on Wednesday.

The Raptors wrapped up a 3-1 Western Conference road trip.

"We had to fight hard for this win, and it's something we can learn from without it hurting us," said DeRozan, who recorded his sixth 30-point game of the season and 86th as a Raptor, second to Vince Carter (91) in team history. "We've had good third quarters this season, and the starters come out and get things rolling."

The Raptors got 21 points and 13 rebounds from Serge Ibaka, plus 20 points and 11 rebounds from Jonas Valanciunas. Kyle Lowry added 12 on 3-of-12 shooting, but it was enough for Toronto to overcome 55 points from Phoenix's second unit, including a career-high 32 points and seven 3-pointers from Troy Daniels.

"We talked about (Daniels) before the game, and he just shot lights out," Toronto coach Dwane Casey said after his team followed up wins over the Memphis Grizzlies and Sacramento Kings by sweeping the season series from the Suns for only the fourth time in team history. "We couldn't get consecutive stops and kept giving them confidence. But we found a way, executed down the stretch, got the line and made our free throws."

With the starters resting, Toronto let most of a 15-point, third-quarter lead slip away. Alex Len's basket capped a 12-0 Phoenix run to pull the Suns within 92-89 with 9:22 left.

"I felt like if we could just keep it to 10 points at the end of the third they'd have to go to their bench and that's where we can kind of claw back a little and we did," Phoenix interim coach Jay Triano said. "We had a couple of little lapses here and there, and we had a tough time with DeMar, who's an All-Star and tough to guard. They had more guys playing better than we did."

The Suns got as close as 111-109 in the final minute but the Raptors (18-8) made five of six free throws in the final 30 seconds to hold them off.

Daniels made seven of his 10 3-point attempts. He has 60 3-pointers this season, third behind Kyle Korver of the Cleveland Cavaliers and Wayne Ellington of the Miami Heat among NBA reserves.

"My teammates were finding me," Daniels said. "I had a couple go in early, which is very important, and the rest were just falling."

The Suns (9-21) lost their fifth in a row and are 0-4 since losing star Devin Booker to an adductor injury. Greg Monroe added 17 points and 11 rebounds, and TJ Warren had 17 points but needed 15 shots to get them.

The Raptors hit five of seven 3-pointers in the first quarter, and DeRozan and Lowry combined for seven assists on Toronto's 11 baskets. Valanciunas and Ibaka combined for 18 points in the quarter, and a 3-pointer by C.J. Miles with 31 seconds left gave Toronto a 37-31 lead.

"Our big played great," Lowry said. "They got a chance to play against their bigs, and they got the better of them tonight. They scored and rebounded the ball extremely well."

Phoenix's reserves outscored Toronto 29-13 in the first half and got a big lift from Daniels. He had nine of his 14 first-half points from three 3-pointers, the last one capping a 7-0 run to give Phoenix a 46-46 lead with 6:16 left in the half.

The Raptors came right back with an 11-2 run, and Lowry's first two points on two free throws with 17.3 seconds left gave Toronto a 58-53 lead at the half.

NOTES: With four injured players, the Suns received an injury exemption and signed G Isaiah Canaan to a contract. Canaan, who did not play Wednesday, has appeared with three other NBA teams, most recently the Houston Rockets. Canaan can play the point, where depth has been a problem since Phoenix traded Eric Bledsoe to the Milwaukee Bucks on Nov. 7. ... Phoenix C Tyson Chandler missed the game due to personal reasons. ... Toronto has played the fewest home games in the NBA (10) and won't have a road trip longer than three games or a road game west of the Central time zone for the rest of the year. ... Suns interim coach Jay Triano was 87-142 in three seasons as head coach of the Raptors (2008-11).