Jaylen Brown's defense set the tone for the NBA Finals

BOSTON – It’s still early in the NBA Finals, but the Boston Celtics seem unbeatable.

Yes, the return of Kristaps Porzingis took the spotlight in Game 1, and rightly so. Dallas could be in serious trouble if they continue to use smaller defenders against Porzingis, who seemed to take it personally and scored virtually every time he touched the ball with an advantage.

What can't be underestimated in Boston's dominant win earlier in this series, however, is Jaylen Brown's hyper-aggressive defense. Or how focused everyone was on defense when it mattered most.

Time and time again this postseason, Boston's defense has collectively turned up the intensity even when the game was on the line. You never know who's going to make an incredible play to spark a run. But you know it's coming.

That's the beauty of this Celtics unit.

Almost every night, a different person makes their big appearance. They've won 13-2 in this playoff stretch in a variety of ways. And while some games have followed a similar story arc, the hero seems to change from night to night.

We've seen Al Horford make seven three-pointers when opponents gave him space. Jrue Holiday has ripped the hearts out of teams with his unmatched defensive instincts. Derrick White has been there in crucial moments to shoot the ball home. Jayson Tatum has led Boston to several victories by setting the table as the best ball handler and attacking downhill to get his teammates open threes.

But it's hard to watch the Celtics over the past two months without being impressed by Brown's poise, control and game-winning plays.

Similar to how he won the Indiana series with loud With numerous defensive stops, he saved the Celtics from a nightmare at the beginning of the Finals.

Brown was the catalyst for Boston's 14-0 run at the end of the third quarter on Thursday. As Dallas cut the deficit to eight points and felt more confident, the Celtics proved they could respond to adversity on the biggest stage. Many wondered if they had the composure to respond to the kind of avalanche that Luka Doncic and Kyrie Irving could unleash.

All Brown had to do was put his foot on the gas and decide that Dallas was only going to score eight points. From his smart defensive moves near the basket to his timely attacks that forced the Mavs to rotate, Brown turned all the nervous energy at TD Garden into absolute chaos by the start of the fourth quarter.

As head coach Joe Mazzulla put it, Brown shows exactly why the Celtics never lost faith in him after last May.

“What you saw tonight is the challenge he set for himself at the beginning of the year,” Mazzulla said after Game 1. “He didn't want to be defined by one thing. He wanted to make plays. He wanted to be a versatile player and keep getting better. His spacing, ball movement, defense with and without the ball.”

It's been an incredible comeback season for Brown, who was largely blamed for last year's collapse against the Miami Heat in the East Finals. He was unsettled and didn't handle it well when Miami caught up in the half court.

Brown turned 27 at the start of this season. The notion that he was a finished product was unfair then. And it looks silly now. If anything, this year proved that stars are still honing their skills in their eighth year and beyond.

Despite receiving a supermax extension over the summer, Brown knew he had to improve his margins to win at the highest level, and the nationwide reaction to his contract only fueled his fire.

Players of this era are more scrutinized than stars of the past. They also can't escape the chatter and face criticism on every platform they use. Although most players say they “tune out the noise” and don't pay attention to it, that's not entirely true. For a few days? Maybe. But not for an entire season or summer. It's just impossible to ignore.

“I would say everything is motivation for him,” Mazzulla said. “I enjoy watching him work. He has a tremendous growth mindset and tries to identify his weaknesses that he wants to improve, improve his strengths and never overlook a detail. I would say he is one of the most motivated guys I have ever seen, just because of the way he works.”

The “details” were on display in all their glory last night.

Arguably the most important possession of the game came with 2:40 left in the third quarter, when the Mavs were down by 13 points. Dallas tried to block Horford and direct him to Doncic, but Holiday fought over the block and stuck to Doncic's hip.

With two players on the ball, Derrick Jones Jr. was able to slide into the middle of the field. Brown knew a lob was coming, was in the low man help position and turned to the side to completely block Jones from making the catch. Then, moments later, he blocked Jones again by turning from the other side:

“JB is unbelievable on the perimeter,” Derrick White said. “He had two great blocks. He can do everything on the basketball court and he has no weaknesses on either side. So, he's great.”

Less than two minutes later, Brown again saved the day as the low man. This time it was Irving who attacked out of a pick-and-roll and targeted Horford. When Irving fended off the block and went downhill, Brown knew it was his responsibility to step up and protect the basket.

Defenders who are in this position have the toughest job on the court. It's reminiscent of what Draymond Green did for Golden State for a decade. Brown covers Daniel Gafford in the dunker position, but also has to move to the side to get help on the weak side.

Eight times out of 10, defensemen or wingers mess up the timing at this point. It's a tough one to master. Perhaps the time Brown spent with Irving a few years ago helped him in these situations because of the many practice repetitions.

“I was the low guy and I was on some of those bigs … you don't want to allow lobs,” Brown said. “That's one thing we emphasize. So I don't want to go too far and allow those lobs. But I was able to play back and forth a little bit and then make some plays at the basket.”

Brown was everywhere on defense in Game 1. He was Luka Doncic's primary defender on 34 possessions, which was 24 more than the next Celtic (Holiday). Boston opted to switch almost every ball screen to Doncic, keep the ball in front of him and stay out of the rotation as much as possible.

This allowed Boston to limit the Mavs' supporting cast from beyond the three-point line. Doncic had just seven assist opportunities because Boston didn't compromise its defense and didn't give shooters any space. Dallas became the first team since the 2007 Cavaliers to finish an NBA Finals game with fewer than 10 assists. The bad news for the Mavericks? Those Cavs got swept.

Given Boston's outstanding performance in Game 1, this should come as no surprise.

The Celtics had the most versatile defense in the league all year, finishing second behind Minnesota in points allowed per possession, but they played with a greater variety of tactics and adapted to their opponents' strengths better than anyone else.

And with so many high-IQ wingers on the field at the same time, they often have to make spontaneous schematic decisions.

“Joe gives us the freedom to trust our instincts,” White said. “Then we know that if someone gets hit, someone is there for us. After that, we just fly around.”

Boston went into this series knowing that they something away from the Mavs. They could not allow Doncic and Irving to slip as scorers while Also He spreads the ball to open shooters and throws easy lobs to Gafford or Dereck Lively.

Their game plan was impeccable in the first half, limiting the Mavs to zero lob completions and zero three-pointers from the corner. These were likely the battlegrounds of this series, so it was crucial for Boston to set the tone.

When the Mavs came back in the third quarter, Mazzulla kept his team calm. They didn't panic or overreact to Luka's magic. Brown recalled what Mazzulla said in the players' meeting when their lead shrank to eight points.

“We said just breathe, the game starts now,” Brown said. “Just breathe. This is a moment where our experience comes out. Just breathe, just keep playing basketball. When you have an open shot, take it with confidence, no turnovers, take care of the basketball and just play our game. We need to get some stops. They made some great shots. Just master the run.”

The Celtics' aggressive defense after that timeout was what ultimately brought the win. But they still had to score points and gain an offensive advantage.

Here, too, Brown's fingerprints were everywhere.

When Dallas Maxi Kleber went after him, he didn't let it bother him. Instead, he used his first step to get a driving angle, got help from the weak side, and made this beautiful pass to Al Horford in the corner:

That's another area Brown has really focused on since last year: limiting his turnovers. His turnover rate during this playoff round (11.4%) is the lowest since 2020. He's smarter with the ball, more decisive on his drives and reads the defense quicker. Of course, there are still a few fumbles in every series, but is any player perfect?

When the Celtics win the franchise's 18th title, I think we'll look back on the explosion in the third quarter of Game 1 as a game-changer. It basically saved them from disaster.

Brown didn't want to let that happen. But he also knows that the next battle could present a different challenge.

“Every game has its own story,” he said. “We just have to stay ready, stay calm and take one game at a time.”