With his running mate DeMar DeRozan under the weather, Kyle Lowry decided to make up for the both of them.

The Raptors guard poured in a career-high 43 points, including a jump shot with four seconds on the clock, to lift Toronto to a 99-97 victory over the Cleveland Cavaliers on Friday, in a thrilling battle between the top two teams in the Eastern Conference.

The No. 2 Raptors (39-18) clinched the season series against the top-ranked Cavs (41-16)

"It's never a surprise for me," DeRozan said of his fellow all-star's performance. "It's moreso entertaining to watch, because I feel like I have the luxury to say 'that's my point guard,' I'm able to watch him to do things like that, make it seem so effortless, and lead us to a victory."

Terrence Ross added 15 points. Jonas Valanciunas, who took a hard elbow to the ribs from James and spent part of the third quarter being examined in the locker-room, finished with 11 points and nine rebounds. Bismack Biyombo chipped in with 11 points as Toronto set a new record with 10 consecutive home wins.

Asked what was more special, his total points or his clutch game-winner, Lowry said: neither.

"I think it was that we won that game," he said. "That is all that matters. I think we grew tonight but now we have to continue to get better."

DeRozan's 500th game was one to forget. The Raptors' top scorer, battling flu-like symptoms all night, had just six points on 1-for-11 shooting.

LeBron James led the Cavs with 25 points. Tristan Thompson of Brampton, Ont., had a game-high 10 rebounds.

A healthy DeRozan would undoubtedly have made a big difference through the first three quarters for a Raptors team that trailed the Cavs for most of the night, and were down 77-68 going into the fourth.

"Felt terrible, but I told myself I was going to go out there and play regardless. It was tough, but I'm happy we got the win," DeRozan said.

But Lowry, who was spectacular all night in the virtual absence DeRozan, led a comeback seemingly by sheer will, and when he got fouled on a bucket right in front of the Cavs bench with 3:59 to play, he pumped a fist and hollered in Cleveland's direction. The Air Canada Centre crowd was delirious, and Lowry's ensuing free throw pulled the Raptors to within five.

A floating jumper from Ross put the Raptors up by one with 2:26 to play, to the delight of the noisy capacity crowd of 19,800 that included Buffalo Bills legend Thurman Thomas, who rifled autographed footballs to fans during a timeout.

A Lowry basket tied the game with 52 seconds left, then JR Smith missed on a three-point shot, and Lowry fired the dagger — a long jumper — to seal the victory in what many were touting as a conference final preview.

The Raptors beat the Cavs 103-99 on Nov. 25 in Toronto, but then were blown out 122-100 on Jan. 4 in Cleveland.

The Raptors shot 51 per cent on the night, and outscored the Cavs 50-34 in the paint.

Toronto looked completely out of sync in a first quarter that saw coach Dwane Casey rotate 10 players in search of a solution. Toronto allowed the Cavs to shoot 57 per cent in the frame and trailed 31-21 going into the second.

"(Lowry) knew that it was on his back. Nobody was having a great game," Casey said. "We were trying to find matchups defensively, somebody to guard LeBron, who is a handful ... It put us in situations where one consistent was Kyle on both ends of the floor. He did an excellent job of leading the team and finishing the game out."

With James on the bench, the Raptors capitalized and took their first lead on a Biyombo layup five minutes before halftime. The Cavs took a 49-45 lead into the break.

Cleveland stretched its lead to a game-high 14 points late in the third.