The Raptors were manhandled by the Celtics, but expect better nights whenever Pascal Siakam rounds out key three

There can be talk about matchups and rotations, and the notion of a fluid starting lineup has been tossed around for years, but there is one undeniable fact about the Raptors.

Their opponents are going to see a ton of the versatile threesome of Pascal Siakam, OG Anunoby and Scottie Barnes on the court at the same time.

Not only are they three of the team’s best players — Fred VanVleet has to factor greatly into any conversation about that — but they give coach Nick Nurse precisely the kind of versatility he wants.

“I would imagine when Pascal gets back into condition, those three guys are going to be the mainstays in the middle of our rotation and taking as many minutes as they can handle,” Nurse said before the Raptors were manhandled 104-88 by the Celtics in Boston on Wednesday night.

Siakam remains on something of a minutes limit as he returns from months of shoulder surgery rehab. He played 30 on Wednesday, up from 25 in Sunday’s return to action, and once again started alongside Anunoby and Barnes to increase the sample size Nurse can use to gauge the threesome’s effectiveness.

It will be tough to gain any great insight from the second game together, though. The Raptors were out of kilter most of the night, unable to keep the Celtics off the offensive glass or sustain any offensive runs.

Siakam struggled — eight points and four fouls — but to think he’d be back in mid-season form in his second game after missing five months is ludicrous.

It’s unlikely he’ll play Thursday when the Raptors finish a back-to-back in Philadelphia.

“I don’t think so,” Nurse said. “I’ll double check with that, but I think that originally going into this … he was just going to play — or not play — back-to-back for a little while.”

This is a learning period, obviously, with a new group playing together for just the second time and still without the much-needed presence of Khem Birch (knee swelling) and Yuta Watanabe (calf strain). There were periods when the Raptors looked discombobulated at both ends, and those stretches are going to take time to even out.

Nurse knows what he wants to discover as the games go along, though.

“I think when it comes down to it, what you really want is three guys who can square people up, look ’em in the eye and be able to guard ’em one-on-one,” the coach said. “And then you’re not having to help as much.”

The three weren’t very effectively defensively, but none of their teammates were, either. The Celtics had 12 offensive rebounds for 21 second-chance points, hit 10 of 27 three-pointers and more than made up for a 32-point clubbing Toronto administered in the second game of the season.

“Really expecting a tremendous effort from them tonight,” Nurse said before the game. “They’ve had a lot of days off. I would imagine they’ll remember that last game a little bit as well. We should get a fired-up Celtics team tonight.”

Toronto’s end game — and it’s still a ways away with 70 games to go in the regular season — is to have the three frontcourt starters give top opponents many different styles to try to attack.

“The really good players, they’re all a little different,” Nurse said. “OG’s maybe down underneath ’em a little more. Scottie’s a little taller. Pascal’s a little quicker. Whatever it is, just give them different bodies to not allow them to get a great rhythm that a lot of these star players and high-scoring players get.

“That’s probably more of what we’re after: multiple bodies on one scorer.”

But even if there is equality among the three, Nurse wants more from Barnes offensively. Not taking shots away from either Siakam or Anunoby intentionally, but finding a way for the rookie to get more field-goal attempts. Barnes had only seven against Brooklyn on Sunday, 19 against Cleveland on Friday. The coach wants his per-game total far closer to the latter.