TORONTO -- Kawhi Leonard poured in a post-season career-best 45 points and the Toronto Raptors opened the Eastern Conference semifinal with a 108-95 victory over the Philadelphia 76ers on Saturday.

On a night that all but Leonard and Pascal Siakam struggled on offence, Leonard shot 16-for-23 and hauled down a team-high 11 rebounds.

Leonard drew chants of "M-V-P!" both after a beautiful spin move around Jimmy Butler early in the night and when he surpassed his previous best playoff points -- set in 2017 versus Memphis -- with a pair of free throws down the stretch.

Siakam added 29 points, but no other Raptor scored in double figures. Kyle Lowry had nine points and eight assists, while Marc Gasol chipped in with eight points, and Danny Green had seven.

JJ Redick had 17 points to lead the Sixers, who had six players in double figures.

Game 2 is Monday in Toronto.

The Raptors led for most of the night, assembling a 19-point by late in the third quarter. Toronto led 92-81 with one quarter to play.

An alley-oop dunk from Fred VanVleet to Serge Ibaka had the Raptors up by 15 points. The Sixers clawed their way to within 11, but Leonard answered with five straight points to put Toronto firmly back in control with an 18-point lead. And when Ibaka blocked a Tobias Harris jumper with 6:18 to play, the Raptors centre waved a hand in the air gesturing for the Scotiabank crowd to cheer.

Leonard, who played just nine games last season with San Antonio because of a serious quadriceps injury, and Siakam were serenaded with a standing ovation when coach Nick Nurse subbed them out of the game with 3:14 to play. Leonard, who was the MVP of the 2014 NBA Finals, has never lost to Philadelphia, a winning streak that stretches back 14 games.

The Raptors shot 51.9 per cent on the night, and held Philadelphia to 39 per cent.

A star-studded crowd turned out for the series opener, included rapper Drake, singer Shawn Mendes, "The Handmaid's Tale" star Elisabeth Moss, Canadian players Cory Joseph and R.J. Barrett, and Vladimir Guerrero Jr., a day after he made his major league debut with the Blue Jays.

Saturday's victory gave the Raptors their first five-game playoff winning streak in playoff history. The series winner faces either Boston or Milwaukee in the Eastern Conference final, which would be Toronto's second appearance (2016 was the team's first).

The Raptors won three of their four games against the Sixers in the regular-season, but both teams say the results are largely irrelevant -- both Toronto and Philly look vastly different from the last time they met on Feb. 5, the day before the NBA trade deadline. The Raptors acquired Gasol at the deadline while Philly traded for Harris as part of a six-player deal.

The Raptors had dispatched Orlando in five games while the Sixers won their opening-round series against Brooklyn 4-1.

Leonard and Siakam carried Toronto on the offensive end, combining for 34 first-quarter points. They were two of just five Raptors who got on the scoreboard in the first half. The Raptors bench, which was so effective last season, went scoreless through the first half.

The Raptors and Sixers met in the second round of the 2001 playoffs. Philly won in seven games when Vince Carter's shot at the buzzer bounced off the rim.

Leonard and Siakam had 17 points apiece on 78 per cent shooting in the first quarter and a pair of Leonard free throws late in the quarter gave Toronto a 14-point lead. The Sixers closed the frame with a 10-4 run, slicing the Raptors' lead to 39-31 to start the second.

Philadelphia kept the pressure on and pulled to within a point four minutes into the second quarter. But the Raptors responded with a 9-0 run to go up by 11. Toronto took a 61-52 advantage into the halftime break.

The series moves to Philadelphia for Games 3 and 4.