Rondae Hollis-Jefferson had 16 points and 10 rebounds for the Raptors, who posted their 14th consecutive home victory over the 76ers.
Embiid shot 0 for 11, missing all four of his shots from 3-point range and going 0 for 3 at the free throw line. He finished with a game-high 13 rebounds.
It was the first meeting between the teams since Kawhi Leonard's dramatic buzzer beater that bounced off the rim four times before dropping, the winning basket in Game 7 of the second round of the playoffs in May. Toronto went on to win its first NBA title, before Leonard left for the Los Angeles Clippers.
This time, the Raptors led 88-87 on a driving layup by rookie Terence Davis with 7:31 remaining in the fourth. Philadelphia's Furkan Korkmaz hit a 3, Horford made a baseline jumper and Harris added a hook shot as the 76ers used a 7-0 run to build a 94-88 lead with 5:16 left to play.
Powell and VanVleet hit 3-pointers that cut the gap to two, 96-94, but Toronto missed three straight chances to tie it. Marc Gasol missed a pair from the line, a jump shot by Siakam missed the mark, and Harris blocked Anunoby's fast-break drive after an Embiid turnover.
Siakam ended Toronto's drought with a three-point play, giving the Raptors a one-point edge, 97-96, with 1:01 left.
Siakam forced a turnover on an entry pass from Simmons with just over 10 seconds remaining to preserve Toronto's lead. VanVleet was fouled and made two shots, giving the Raptors a three-point cushion.
Harris and Simmons missed 3-pointers before Siakam finished it with a thunderous dunk.
For the first time in his career, Embiid didn't score in the first half. He missed all four field goal attempts and came up empty on a pair of free throws.
76ers: F Kyle O'Quinn (left calf) was not available.
Raptors: G Matt Thomas (fractured left finger) was not available. Thomas was one of six Raptors sidelined by injury, including G Kyle Lowry (left thumb), F Serge Ibaka (right ankle), C Dewan Hernandez (right thumb), F Patrick McCaw (left knee), and F Stanley Johnson (left groin). ... Coach Nick Nurse said Ibaka could return this weekend. After hosting the Knicks on Wednesday, Toronto visits Orlando on Friday, before hosting Utah on Sunday.
BEEN A WHILE
The 76ers haven't won a regular-season game north of the border since Nov. 10, 2012, when they beat Toronto 93-83. Philadelphia's leading scorers that night were Jrue Holiday, Nick Young, and Thaddeus Young, each of whom scored 16 points. At the time, it was Philadelphia's fifth win in six meetings with the Raptors.
76ers: Host Sacramento on Wednesday night.
Raptors: Host New York on Wednesday night.
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