TORONTO -- Kyle Lowry scored 15 of his 32 points in the fourth quarter to lift the Toronto Raptors to a 105-91 victory over the Boston Celtics on Friday.

Luis Scola added 17 points, while DeMar DeRozan finished with 15. Bismack Biyombo, who a night earlier had set a franchise-record with 25 rebounds, grabbed a team-high 11 as the Raptors (47-21) won for the 12th time in 15 outings.

Isaiah Thomas scored 20 points to lead the Celtics (39-30), in their fourth consecutive loss, and sixth loss in their last seven trips north to Toronto.

Canadian Kelly Olynyk, playing his second game after missing 12 with a shoulder injury, had five points and four rebounds for Boston.

The Raptors, who took a seven-and-a-half game lead over Boston into the night, raced out to a 19-point lead and looked headed for a rout of their Atlantic Division rival.

But coach Dwane Casey has lamented several times this season about his team's inability to put opponents away, and sure enough, by the end of the third quarter, the Raptors had allowed Boston to creep back to within five points.

Lowry came up big in the fourth, scoring 10 points in the first five minutes. His second consecutive three-pointer put the Raptors back up by 17 points with 7:08 to play. The all-star guard kept up the late-game heroics, stretching Toronto's advantage to 18 points with another three with four minute left to play that delighted the capacity crowd of 19,800 at the Air Canada Centre.

Toronto shot 48 per cent on the night, and held a narrow 40-37 advantage on the boards.

The Raptors, who continue to chase the Cleveland Cavaliers for first place in the Eastern Conference, face the Celtics again Wednesday in Boston.

The Raptors roared out of the gate, and backed by Scola's early scoring extravaganza, took a 30-14 lead into the second quarter. Boston's 14 points were a season-low for first-quarter scoring by a Raptors opponent this season.

The Raptors stretched their lead to 19 points early in the second, and took a 55-41 advantage into the third.

The third quarter was a nightmare for the Raptors, who looked nothing like they did in the first half. Turnovers proved costly, and when RJ Hunter hit a three-pointer with three-tenths of a second on the clock, it cut the Raptors' lead to just 79-74 with a quarter left.

The Raptors host Orlando on Sunday.