BOSTON — Karl-Anthony Towns didn’t make a massive impact in his Knicks debut. 

The four-time All-Star center finished with a quiet 12 points and seven rebounds in the Knicks’ season-opening blowout loss Tuesday night to the Celtics. 

Acquired in a blockbuster trade to man the middle following the absence of free agent Isaiah Hartenstein and injured Mitchell Robinson, Towns had zero blocked shots and finished minus-18 over 24 minutes. 

“It’s not one guy,” Tom Thibodeau said when asked afterward about Towns’ first game with the team. “Obviously we have to be better. So we’ll look at the film and the adjustments we have to make.” 

Still, the Celtics targeted Towns often on screens and they connected on an NBA record-tying 29 3-pointers in the game, including eight by Jayson Tatum, six by Derrick White, five by Jaylen Brown and three by veteran center Al Horford. 

“You’ve gotta give credit where credit is due. They hit a lot of 3s, they hit a lot of shots,” said Towns, who was acquired in the deal that sent Julius Randle and Donte DiVincenzo to Minnesota just before the start of training camp. “You take 61 threes in a game, they definitely shoot the ball, so we gotta be better defensively. I just think that we just didn’t do enough defensively to give ourselves a chance to win the game. 

“We’ve just gotta do a better job of executing on that end. Our defensive identity is what’s gonna give us a chance to do something great. Offensively, I think we showed tonight we can score, we’ve just gotta play defense.” 

With Towns and Mikal Bridges new to the Knicks starting lineup, the Celtics’ cohesion and familiarity with each other was hard to miss. 

“I think when you shoot the way they shoot, the numbers tell you how great their offense is,” Thibodeau said. “And so you have to go into the game with the awareness — it’s going to create great effort on every play, great concentration. We knew that going in. 

“You have to be strong defensively and we have to be strong offensively. So that’s the biggest thing.”