This is going to be short and terribly un-sweet. Let's try to pinpoint what went wrong for the Raptors, and then discuss a couple silver linings.
What Went Wrong
Practically everything. Moving on.
You don't believe me?
The offence: graded out at an ORTG of 88.6. Kyle Lowry was 4-for-14 for only 8 points, missing all 7 of his threes. DeMarre Carroll scored two points. Bismack Biyombo and James Johnson were the Raptors' second and third highest scoring players. We'll leave it at that.
The defence: graded out at a DRTG of 120.4. LeBron James went 11 of 13 from the field. Including 11 of 12 in the restricted area. He took one three and the rest of his shots were in the restricted area and he scored 24 points. Kyrie Irving scored 27 points on 11 for 17 shooting. Including 6 of 8 in the restricted area. That's 20 layup attempts given up to the two best scorers on the Cavs. Not a formula for success.
The boards: Toronto grabbed 23 rebounds. Cleveland grabbed 45. Toronto managed to grab 10% of all available offensive rebounds. Cleveland managed 35%. Bismack Biyombo ended up with four total rebounds. Patrick Patterson had two.
Some Odd Decisions
Everyone and their uncle knows by now that the Raptors absolutely cannot survive without Lowry or DeRozan on the floor. So at the outset of the 2nd quarter, with the Raptors still within 5, it was odd to see a lineup of Joseph, Ross, Johnson, Carroll and Biyombo out there. Luckily they only played 82 seconds together. Unluckily, they gave up a 6-0 run in those 82 seconds (for the curious, that's a final score of 210-0 over 48 minutes).
This is becoming a bit of a recurring story in Game 1 of each series. That 6-0 run sparked the Cavs and started a 16-2 run to start the quarter. Might be best to avoid that in the future.
But How About James Johnson
Look who is still playing meaningful minutes. He had perhaps the strongest night of any Raptor player, posting 10 points (on 6 shots), 4 boards, a steal and an assist in 19 minutes, while being only a -6 in that time (while other players who played at least 19 minutes like JJ were all at best a -15). Note that this means he broke even in all minutes outside of the above mentioned no-KL-no-DD lineup.
Riding and Dying with Demar DeRozan
Good and bad here.
Good: he made a lot of shots, especially compared to his playoff norms this year. 18 points on 17 shots, and racked up 5 assists (which was very good to see, only the second time he's hit 5 assists in the playoffs this year).
Bad: he took a lot of bad shots. He took 1 three, 2 shots at the rim, and 3 more in the paint. And 11 midrange jumpers. There was a lack of aggression for most of the game that saw him stay out of the paint (and subsequently, entirely off the line -- he attempted zero free throw attempts this game). Even with a lot of those shots falling this game, he barely managed a point per shot, and the odds are those jumpers don't fall at that rate again (7 made midrange jumpers).
The team needs to get back to what it has had tremendous success with -- protecting the rim and rotating out to shooters after. It's a dangerous strategy against a team like Cleveland that can shoot so well, but giving up layups all game long is not the answer, obviously.
The team needs better offensive perfomances from their stars and role players, and setting an aggressive tone instead of settling for jumpers is a must.
And the team absolutely must hold their own on the boards against the Cavs. That is an offence you cannot afford to give extra chances to, and without pressure on the glass in the Cavs' end, the transition game will remain wide open for them.
The Raptors have bounced back and won every game following a loss this post-season (6-0). It will require a tremendous effort and a lot of adjustments to the game plan to manage to keep that streak alive.
All stats per NBA.com.