The Celtics tied a franchise postseason record for made 3-pointers in Game 1 of their first-round playoff series. They blew out the Miami Heat by 20 points and led by as many as 34.

What must they do Wednesday night to avoid a Game 2 letdown? Ratchet up the physicality against their underdog opponents.

“Better is what we did with higher intensity and higher physicality,” Celtics coach Joe Mazzulla said after Tuesday’s practice at the Auerbach Center. “I think that’s what Game 2s call for.”

Top-seeded Boston boasts a far more talented roster than No. 8 seed Miami, especially with Heat star Jimmy Butler expected to miss the entire series with a knee injury. That disparity showed in Sunday’s opener, with seven different Celtics sinking multiple threes and the team going 22-for-49 (44.9%) from deep in a 114-94 victory at TD Garden. The Heat went 12-for-37 (32.4%) from three, and half of their makes came in the fourth quarter with Boston up big.

The Celtics’ intensity did wane at times, however. The Heat battled back from a 17-2 deficit in the first quarter and outscored Boston 35-23 in the fourth.

“If you think that you’re not going to see a different version of Miami (in Game 2), then you’re kidding yourself,” Mazzulla said of the team that eliminated the Celtics in two of the last four NBA postseasons. “So at the end of the day, it’s about giving what that game needs and having the expectation that it’s just going to be a fight, and just go get ready for a fight.”

Jaylen Brown reiterated that same word — “fight” — multiple times when describing what the Celtics must do to take a 2-0 lead in the best-of-seven series.

“Every game is a fight,” said Brown, who had 17 points and eight rebounds in Game 1. “You’ve got to win the game, and you’ve got to win the fight. Both of those things are important, and we embrace both. …

“We’ve got a good game plan (for Game 2). We feel good about it. But we’ve got to win the fight. I can’t stress that enough.”

Speaking of fights, one nearly broke out on the court in the final minute of Game 1 after Heat forward Caleb Martin upended Celtics star Jayson Tatum while the latter was jumping for a rebound. Brown and Kristaps Porzingis rushed in to confront Martin, leading to a brief scuffle beneath the basket.

Brown said he sent a stern message to Martin, who was a surprise standout in Miami’s Eastern Conference finals upset of Boston last season. Martin scored four points in 29 minutes on Sunday and was 0-for-4 from 3-point range.

“I just told him to watch that, making sure it’s basketball plays being made out here,” Brown said. “We know they like to play hard and be physical, but there’s a line. So, making sure we’re not crossing the integrity of the game. I just told him to watch it.”

He added: “Seeing a guy go down, I’ve got my guy’s back 10 times out of 10.”

Game 2 at TD Garden tips off Wednesday night at 7 p.m. ET.

Tatum fine after fall

Tatum was a full participant in Tuesday’s practice, according to Mazzulla, showing no ill effects from his late-game tumble two days earlier. Mazzulla also said he didn’t believe Martin’s hard foul was deliberate.

“I don’t think it was intentional,” Mazzulla said. “It’s obviously something that people can latch on to for two days, but I didn’t think it was really that intentional. I thought it was just, it is what it is.”

Despite struggling from beyond the arc (1-for-8), Tatum registered the first playoff triple-double of his career in Game 1, finishing with 23 points, 10 assists and 10 rebounds. Porzingis called the five-time All-Star’s performance “beautiful” and “perfect.”

Mazzulla unbothered by awards snubs

Despite boasting easily the NBA’s best record, no Celtics were among the finalists for the league’s seven end-of-season awards, which were announced Monday.

That lack of individual recognition didn’t bother Mazzulla one bit.

“No, not at all,” Boston’s head coach said. “I think it’s beautiful. … Why would you get an award for the past?”

Mazzulla said the snubs haven’t been a topic of conversation around the Celtics’ facility.

“The great thing about this team is I think from Day 1, we’ve appreciated the individual awards that we’ve gotten from the Player of the Month, Staff of the Month and whatnot,” he said. “But at the end of the day, I think one of the biggest strengths of this team is they haven’t had that agenda. None of the guys have brought it, and I don’t think it’s important at all because we’re all focused on what we need to do as a team.”

Oklahoma City’s Mark Daigneault, Minnesota’s Chris Finch and Orlando’s Jamahl Mosley were the three finalists for NBA Coach of the Year. Mazzulla was a finalist last season.