Brooklyn Nets rookie Mikel Brown Jr. had his first NBA marquee moment on Tuesday vs. the Boston Celtics. Then came his first major learning experience.

After starting 0-for-6 at TD Garden, Brown scored 16 points in the fourth quarter and overtime, nearly willing the Nets to victory. With Brooklyn down three with 2.7 seconds remaining, the rookie drained a fading corner three to force overtime.

Mikel Brown Jr. drains a fading corner three to tie the game with 0.2 seconds remaining.

The first marquee moment of the rookie’s career. This TD Garden crowd is stunned.

We’re headed to overtime.

Wow. pic.twitter.com/1wQ64KyjAs

— Erik Slater (@ErikSlater_) October 28, 2026

However, his inexperience proved costly during a decisive closing sequence.

Up by one with 6.1 seconds left, Brown caught an inbounds pass near the rim and went up for a layup instead of pulling the ball out. He missed, and Boston grabbed the rebound. Brown then got screened and switched onto Jayson Tatum when he shouldn't have, and the Celtics star drained a game-winning buzzer-beater.

Mikel Brown Jr. opted to go for the layup with the Nets up 1 with 6.1 remaining in OT and missed.

Jayson Tatum hit a buzzer beater on the next possession for a Boston victory.

The Nets are 0-4 to start the season. pic.twitter.com/xPLAJajQYp

— SNY Nets (@SNYNets) October 28, 2026

JAYSON TATUM.

GAME-WINNING @TISSOT BUZZER-BEATER TO SEAL IT FOR THE CELTICS IN OT 🤯😳

🚨⏰Everyone Gets 24 pic.twitter.com/UwK9VKPJeq

— NBA (@NBA) October 28, 2026

Brown took accountability for his costly layup attempt following the loss.

“I mean, I did see the open lane, and I thought I had a layup,” Brown said. “But the ball was kind of already slipping out of my hands, and [Paul George] was already coming towards my right side. So I felt like if I didn't go up with it, I kind of was gonna fall out of bounds. So that was my last resort, in all honesty, but I can't make an excuse. There's a lot of plays down the stretch that I messed up on, that I take full accountability for, and I'm gonna be better.”

What was the message from the Nets coaching staff before the play?

“It was discussed to just try to get it in and try to kill time. That definitely was discussed, but like I said, it's just mistakes down the stretch that I just can't make. I just can't do that,” Brown said.

Mikel Brown Jr. on attempting the layup in the final seconds up one rather than pulling the ball out:

“I did see the open lane, and I thought I had a layup, but the ball was kind of already slipping out of my hands, and PG was already coming towards my right side. So I felt like… pic.twitter.com/napZrAEk8e

— Erik Slater (@ErikSlater_) October 28, 2026

The Nets still had an opportunity to win the game with a stop.

Mikel Brown Jr. using late-game mistakes during Nets' loss to Celtics as learning experience

Boston Celtics forward Jayson Tatum (0) celebrates his game winning shot at the end of overtime to defeat the Brooklyn Nets at TD Garden.
Winslow Townson-Imagn Images

However, Jordi Fernandez revealed his players made a crucial mistake on the final defensive possession. After Brown, who was covering Payton Pritchard, got screened by Tatum, who Noah Clowney was covering, the Nets teammates switched against their coach's advice.

“We're not supposed to switch there because we wanted to keep a bigger body on [Tatum]. We did switch… And he got a shot that he could make,” Fernandez said. “We wanted to maintain the matchup on Tatum with Noah Clowney, because he's big, and we switched it, and we should not have switched it… And then Keon [Ellis], who was on the ball, he was supposed to track and contest that or help a little bit because we knew that most likely the shot was for him. It's a guessing game at that point. I think [the Celtics] did a good job. We didn't really follow [the game plan], and they made it a tough shot. We got to move on.”

Jordi Fernandez on the final possession of the game:

"We're not supposed to switch there because we wanted to keep a bigger body on him. We did switch. He bumped contest and he got a shot that he can make… We wanted to maintain the matchup on Tatum with Noah Clowney because… pic.twitter.com/tQI7Ujy6vR

— Erik Slater (@ErikSlater_) October 28, 2026

The final sequence wasn't Brown's first costly defensive miscue. The rookie scored a game-tying layup with 44 seconds left in regulation, but Derrick White got an and-one on the other end before hitting his game-tying three in the final seconds.

Did Fernandez consider subbing Brown out on the final overtime possession for another player, like 6-foot-8 wing Josh Minott?

“Yes, but when guys haven't played the whole game, and then they have to go guard that possession, I just didn't want to do it,” Fernandez said. “So that's on me if that's what I'm completely comfortable with. Also, [Mikel] has to go through this in other games, and it's important for him.”

Article Continues Below

Brown also took accountability for switching on the final possession.

“We're supposed to stay home, especially on Tatum; keep Noah on Tatum. I kind of got caught up because I didn't know which way Payton was gonna go, and then we ended up switching. I completely put the blame on myself. I can't just break the coverage like that. I take full accountability for it. It's gonna be hard watching the film tonight, and I'm just gonna learn from it. Let's try to get the next one.”

Despite Brown's late miscues, his performance was encouraging. The 6-foot-4 guard's confidence and clutch shotmaking were as advertised. While he shot 5-of-17 from the field and 4-of-11 from three, he had three triples rim out in overtime that would've essentially iced the game.

The Nets received contributions across the board, with six players reaching 15 points. Michael Porter Jr. scored 27 points on six made threes and had two key blocks down the stretch. Despite struggling early, Randle added 24 points, including several big buckets in overtime.

Sophomore Nolan Traore got his first start of the season, finishing with 15 points and three assists on 6-of-9 shooting in 24 minutes before cramping forced him out. Chaney Johnson and Moe Wagner added 15 points apiece off the bench while combining to shoot 11-of-18 from the field and 5-of-10 from three.

However, the Nets' lack of a defensive stopper proved costly. Tatum finished with 40 points while attempting a career-high 22 free throws.

“At the end of the day, what I take out of this game is the competitiveness, playing as a unit. We played the right way. We look like a good team out there,” Fernandez said. “We executed late at the end in late-game situations… and all those things are important to be in those situations. Obviously, on that layup with Mikel, you want to dribble it out because you want to take more time off the clock and then they'll foul you. Good intentions, if you go for the layup, you've got to make it. But even if you make it, it's still a one-possession game. But he'll learn from it. I just told him. He was not happy with himself, and it's a lot. But the kid was also a reason we were there. He got it going, and he showed that when the big lights are bright, he can perform. So, a lot of good things, and we've got to move on to the next one. I know it's tough, but I take the positives.”