The Celtics make adjustments and get the win over the Nets in overtime

For the Celtics to ultimately win this game against the spirited Nets, they had to match Brooklyn’s grit and intensity. The pretty basketball with free-flowing three-pointers failed completely on Friday night at TD Garden.

Since those shots weren’t falling, the Celtics had to adjust. They had to become the stronger playing team; They had to match the intensity of Brooklyn because the Nets played without fear, they played like a well-coached team that was hardly intimidated by the reigning world champions.

The Celtics have to get used to this, weaker teams play above their pay grade, challenge them defensively, chase every rebound and every loose ball, strike first and hope to keep the game going until the final minutes.

This was the case as the Nets outplayed and outplayed the Celtics for three quarters. But the Celtics withstood the attack, adjusted mentally and schematically as those threes bounced off the rim, and survived with a 108-104 overtime win.

The sluggish game started at the top as the Celtics fell behind 12-0 and 16-2. It would be tough, but what this club has learned from the bad defeats of the past is how to respond to adversity.

The Celtics were 14 for 53 from the 3-point line. Sam Hauser, a career 41.8 percent 3-point shooter, missed nine of his first 10 attempts and many of them were open. But Jayson Tatum kept his faith and fed Hauser in the right corner for a three-pointer with 2:06 minutes left in regulation.

Maintaining that belief and also matching the intensity of the Nets secured the game. It’s okay to achieve victories. It’s an 82-game season. The Celtics won’t be on the road every night. The goal is to be open-minded and versatile enough to do your best when you’re not doing your best.

“I don’t think the guys are making the decision to say, ‘We’re going to let them outdo us,'” Mazzulla said. “Sometimes you just have to give the guys some perspective. Sometimes we play well and things just don’t go the way they normally go. The other team has a great coach and great players too.

“I just thought we made enough plays to somehow get it done. It’s a testament to the team because you have to find ways to win ugly and that’s how it is over the course of a long year.”

It has become clear that the Celtics will need full health to be as consistently dominant as they desire. Jaylen Brown missed his fourth straight game with a left hip flexor strain, while Luke Kornet sat with hamstring soreness. And for the second time in a row they were surprised by the intensity of their opponents. They stumbled into this game completely disinterested and the sellout crowd followed suit.

“This is not an excuse at all, but a perspective. One of the reasons we were good last year is because we win games like that,” Mazzulla said. “When you’re down three rotation players (including Kristaps Porzingis), you have to find ways to win. Nobody cares that we have boys outside. It doesn’t matter and everyone in the locker room needs to know that we have the expectation of winning regardless of who is on the field. If (expletive) isn’t what you want, you’ll just have to figure it out. I like their mentality. Last year we had about 18 of these (type of games) and this was one tonight.”

It’s difficult to change your mentality and become the tougher team in the middle of the game. The game rewarded the Nets in the first three quarters because they wanted to win the game more. They beat the Celtics along the boards and got big shots from scorer Cam Thomas, while former Celtic player Dennis Schroder cut into the paint for layups.

The Celtics looked bad in the first half against the Warriors on Wednesday and not even 72 points in the second half could lead to the win. This time they won the game with defense and timely shooting, including a three-pointer from Al Horford in overtime that gave Boston the lead for good.

Tatum led Boston with 33 points and added 9 rebounds, 6 assists and 2 steals. The Nets constantly held him captive, pushed him out of his spots and forced him to make the right plays, such as the corner pass to Hauser for the go-ahead three-pointer in the fourth period.

“(Mazzulla) always talks about how it’s not going to go the way we expect,” Tatum said. “The Nets are not the same team they were last year. They play differently. They have a different coach (Jordi Fernandez). You play with more energy and freedom. (Mazzulla) always says expect it to be unexpected. How will we react? How do we find a path to victory?

“It’s not about breaking away from the things that make us who we are. We still have to play the way we think is right.”

Hence the 53 3-point attempts on a night where the Celtics were 6 for 33 alongside Tatum and Payton Pritchard. The Celtics will always be themselves. They’ll never back down from their plan, but what they’ve done in the Mazzulla era is find ways to win when they’re not playing nearly their best. And that is a practical skill.

Gary Washburn is a Globe columnist. He can be reached at [email protected]. Follow him @GwashburnGlobe.