TORONTO -- The Golden State Warriors had to work hard for it, but the result was the same as it has been all season.

After a fierce struggle down the stretch, the Warriors won their 21st successive game to open the season, 112-109 over the Toronto Raptors on Saturday.

It took 44 points from guard Stephen Curry, who came up with 15 points in the fourth quarter.

"It's really been good -- 21 different challenges and we've been able to separate each individually and figure out different ways to win," Curry said.

The Raptors (12-9) received a career-high 41 points from point guard Kyle Lowry, who added seven assists.

"That's a great NBA win right there," Warriors interim coach Luke Walton said. "That Toronto team is very talented and they were playing at a high level today."

"They are 21-0 for a reason," Raptors coach Dwane Casey said. "Kyle had a good offensive (game). But again those moments of truth, where a rebound, a box out, loose ball ... layups, free throws, whatever it is -- you have to make those plays in those moments to beat a great team."

Guard Klay Thompson added 26 points for the Warriors, while forward Draymond Green had 16 points and nine rebounds. Center Festus Ezeli scored eight points and grabbed 10 rebounds.

"I think everybody's staying in the moment," Curry said. "That's the biggest thing for us: every night trying to lock in and focus and bring the effort. We might not play our best game, but we find a way to win."

Guard DeMar DeRozan added 16 points for the Raptors, who have lost two in a row. Center Lucas Nogueira added 14 points, forward Luis Scola had 10, and guard Cory Joseph and forward DeMarre Carroll added nine each.

"It's tough, especially when the game came down to a couple of mistakes that we made. If it was free throws, turnovers, missed rebounds, we would've had the game," DeRozan said.

The Raptors, who trailed by as many as 13 points in the first quarter and by 10 points at halftime, took the lead at 85-84 in the fourth quarter.

Toronto led 98-95 when Scola made two free throws with 4:13 to play, but Curry tied it with a 3-pointer.

Curry's 3-pointer with 2:33 to play put the Warriors ahead 102-100. After the Raptors tied it, Green made two free throws for a 104-102 Golden State lead with 1:25 to play.

DeRozan made one of two free throws to cut the lead to one. Curry made two foul shots before Lowry made a driving layup with 44.2 seconds left, but he missed a free throw and the Warriors led by one.

Curry made two free throws with 18.2 seconds left for a 108-105 lead. Lowry cut the deficit to one with a basket before Thompson made two free throws with seven seconds to play.

The lead was down to one when Scola made two free throws with 6.2 seconds left. Curry made both his free throws and Toronto turned over the ball with 3.3 seconds to play.

Curry scored 16 points to lead Golden State to a 32-21 first-quarter lead.

Lowry scored 11 points in the second quarter and the Raptors took a 43-42 lead on a running dunk by DeRozan.

Thompson hit two 3-pointers in the final minute of the second quarter to help the Warriors take a 59-49 lead at the intermission.

The Warriors' lead was cut to 76-73 in the third quarter when Nogueira put in a dunk with 2:52 left.

DeRozan's layup with 51.9 seconds left in the quarter cut the margin to two. Curry's jumper gave the Warriors an 83-79 lead after three quarters.

Nogueira's dunk early in the fourth quarter tied the game, 84-84.

Forward James Johnson hit one of two free throws to give Toronto the lead.

Thompson's 3-pointer with 7:53 to play gave the Warriors an 87-85 lead. After Toronto tied the game, Curry hit a 3-pointer and guard Shaun Livingston scored on a layup to give Golden State a 92-87 lead with 6:31 to play.

DeRozan's driving reverse layup reduced Golden State's lead to one and Lowry gave Toronto a 96-95 lead with 4:53 left.

Lowry said there is little room for error when playing the Warriors. "It's super small," he said. "The way they shoot the ball, the way they move the ball and the way Draymond (Green) plays, they are the champs and it's as simple as that."

Walton said, "That's our 11th win on the road this year. So you have to give the guys in there so much credit for, even in games where we really don't have it, (finding) a way to win."

NOTES: The Raptors celebrated the late Nelson Mandela, former president of South Africa and Nobel Peace Prize winner, with tributes before and during the game. ... The game marked the first time this season that the Raptors have played twice in a row at home. ... The Warriors defeated the Raptors 115-110 in the first meeting between the teams Nov. 17 at Oracle Arena. ... The Warriors entered Saturday with a 20-0 record to equal baseball's St. Louis Maroons of the Union Association in 1884 for the best start to a season among the four major U.S. sports leagues. ... The Raptors continue their six-game homestand Monday against the Los Angeles Lakers. ... Golden State will play the fourth game of a seven-game trip Sunday at Brooklyn against the Nets.