The 76ers: Philadelphia 76ers led the Celtics by as many as 22 points in the second quarter, but still managed to choke in the second half to lose in London by double-digits.
Offensively, the Cavs shot 38 percent from the field, got nearly no production from their starting backcourt and canned just six three-pointers, half their season average.
LeBron James had 26 points for Cleveland (26-15) and led all scorers in the game.
The four-time MVP also finished with just a season-low single assist - but his fellow starters have to take some of the blame for that, with Kevin Love, J.R. Smith and Isaiah Thomas struggling for the second straight game.
Fred VanVleet came off the bench with 22 points, including 6 of 8 from three-point range, as Toronto dropped Cleveland 133-99 on Thursday night.More news: Computer chip flaws: what users need to know and do
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For the first time in his National Basketball Association career, James has lost consecutive games by 25-plus points following Thursday's forgettable result.
Love grabbed a team-high nine boards, but was just 2-of-8 from the floor for 10 points. Jakob Poeltl tallied 12 points and 12 rebounds for the Raptors.
It's the 615th game on the schedule, and one far more interesting than the 616th game of the season between the Clippers and Kings, which kicks off the second half of the season. Cleveland heads to IN next for a game against the Pacers Friday night. "It's a good test for us". "This is just us".
Although the Cavs were sharper in the third, the Raptors added to their lead, outscoring the Cavs 35-32 in the quarter to make it 100-72. "I don't know where it kind of went wrong or what happened, but we have to have to try to pick it back up and find it". "But he's moving around, moving much better than he was the other day".
Thomas has averaged 19.7 minutes per game in his three contests since returning from a hip injury that sidelined him for the first 36 tilts of the season.