Jaylen Brown continues to be a beast for the Celtics and other takeaways from Game 1 of the NBA Finals

BOSTON — Jaylen Brown is a man on a mission this postseason, and he’s getting even better now that the NBA Finals have arrived. Brown was everywhere for the Celtics in Game 1 on Thursday night, leading the charge in a 107-89 victory over the Dallas Mavericks.

Big threes? He hit a few. Stellar defense that wore out Luka Doncic? Yep, he did that, with some emphatic rejections on other Mavs too. And then there were his dunks — angry, ferocious dunks.

After claiming MVP of Boston’s Eastern Conference Finals sweep over the Pacers, Brown looks determined to add another MVP trophy — and championship ring — to his collection. But Game 1 was much more than Brown’s dominance of Dallas. Here are all the takeaways from Boston’s victory to start the NBA Finals.

Angry dunks from Jaylen Brown

We have to start with those JB dunks. The man is a poster producer.

Goodness, Jaylen. Those guys have families!

And then there was this stretch in the second quarter when Brown hit a three, stole the ball from Luka Doncic, and then coasted in for another jam.

Brown was, simply put, awesome in Game 1. His 22 points off 7-for-12 shooting led the way for a balanced Celtics offense, and he added six rebounds, three steals, and three blocks (more on those in a minute) for a healthy Game 1 stat-line.

What does such a monster night mean to Brown?

“It means nothing. It’s just be ready for the next one,” he said.

That is one determined man right there. This certainly feels like the postseason of Jaylen Brown.

Porzingis is back, and he’s back big

Kristaps Porzingis returned after missing 10 games and nearly 40 days of action. He looked a little gassed late in the game, but showed no rust when he entered the game early in the first quarter.

The big man beat his former team with midrange jumpers, deep threes, and some incredible defense in the paint. He scored 11 points in the first quarter to go along with a pair of blocks, and he altered a number of layup attempts by the Mavs to help the Celtics build a big lead.

Porzingis moved well throughout his 20:34 on the floor, and finished 8-for-13 overall and 2-for-4 from downtown. He pulled down six rebounds and blocked three shots in his return.

The Celtics were real good without Porzingis, but they’re scary good with the big man back in the mix.

The Celtics almost let the Mavericks back into Game 1

Boston led by as many as 29 points in the second quarter. But a poor close to the first half and a poor start to the third quarter made things really uncomfortable inside TD Garden, as Dallas cut that lead to just eight points.

Dallas scored the final seven points of the first half, with five of those points coming from Doncic, and the the Celtics let the Mavs go on a 22-9 run to start the third quarter. The C’s took their foot off the gas on defense and stopped moving the ball on offense, which is usually a recipe for disaster for Boston.

At least they woke up when Dallas made it a single-digit game and went on an 8-0 run to take control again. The Mavs only won the third quarter by one point, 25-24, thanks to Boston’s big response, and they never really had a chance after that.

It was frustrating that the Celtics nearly let the Mavs back in, but they once again responded in a big way and closed out the game.

The Celtics threw a block party at TD Garden

The Celtics rejected nine shots on Thursday night, setting a new franchise record in an NBA Finals game. Porzingis and Brown blocked three each, Al Horford sent a pair of Dallas shots back, and Jayson Tatum had a rejection as well.

Look at this defensive intensity from Brown late in the third, which helped the Celtics get rolling again.

Blocks were just one part of Boston’s dominating defense in Game 1. The Celtics held the Mavs to just 89 points, which was the fourth-fewest for Dallas this season. Boston also took away the three-ball, as Dallas was just 7-for-27 from deep.

Boston’s balance vs. Dallas’ Doncic-centric offense

Each of the Celtics’ top six players scored in double digits, and Sam Hauser nearly made it seven players as he broke out of his shooting slump and had eight points off 3-for-4 shooting. (He also played some solid D on Doncic in the first quarter.)

Doncic had 30 for the Mavs, but he needed 26 shots to get there. No one else on Dallas had more than 14 points, and those came from P.J. Washington. With just about everyone in a Dallas uniform struggling to hit shots, Doncic had just one assist, setting a new career-low for him in the playoffs. Dallas as a team had just nine helpers all night.

The Celtics’ defense made Luka work for everything on Thursday night, and pretty much shut down everyone else. A lot of the credit goes to Brown, Jrue Holiday, and Derrick White, but it was truly a team effort for Boston.

The Celtics’ defense completely took Kyrie Irving out of Game 1

Irving has now lost 11 straight games to the Celtics. He rarely looked comfortable in Game 1, scoring just a dozen points off a woeful 6-for-19 shooting from the floor. He missed all five of his three-point attempts despite having some good looks. He committed three turnovers, including a very un-Kyrie-like turnover where he dribbled the ball off his foot.

The Celtics’ defense completely threw him off his game, and it essentially left Luka on an island.

Jayson Tatum had a turnover issue in Game 1

Tatum never really got going offensively, and finished with 16 points off 6-for-16 shooting. He impacted the game elsewhere with some solid defense and 11 rebounds, but he also coughed the ball up six times.

It was hard not to have flashbacks to Tatum’s turnoverfest in the Finals two years ago, but at least the Celtics won on Thursday night. But Tatum really needs to clean it up — and start hitting some shots.