Al Horford missed an open corner three that would have given the Celtics the lead with 34.9 seconds left, but rookie Tristan Da Silva didn’t miss his opportunity, nailing a corner three with 9.9 seconds left to give the Magic a 108-104 emotionally charged win at Kia Center.

Orlando was missing three of its top four scorers — Franz Wagner, Mo Wagner, and Paolo Banchero — and started Da Silva and two-way guard Trevelin Queen, and they combined for 35 points and seven 3-pointers.

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The Celtics were completely stymied by Orlando’s aggressive defense that ran them off the 3-point line. They were 5-for-19 shooting with seven turnovers in the third quarter, wasting a 15-point lead. The Celtics were overwhelmed by the Magic’s switching and trapping and were relegated to attacking the rim or settling for twos.

Boston was just 8 for 33 from the 3-point line, both season lows. The eight makes were the fewest since Celtics were 5 for 22 in a Feb. 27 win over the 76ers.

Jaylen Brown scored 35 points but also committed five of the Celtics’ 18 turnovers.

“Definitely a physical game. Give credit to Orlando, we should have met the physicality a little bit better,” Brown said. “I think it’s a good preparation game. Things wasn’t going our way and we felt like the officials was one-sided and I felt like this was good for us, to see that more, get used to that more, get more comfortable with that level and environment. We’ll watch it and we’ll be better.”

Kristaps Porzingis added 17 points but was 2-for-10 from the field and his frustration nearly boiled over when he got into a scrape with Orlando’s Jalen Suggs and Goga Bitadze with 3:36 left. Suggs and Porzingis exchanged words and then Bitadze shoved Porzingis, and then Suggs also followed with a shove.

Porzingis and Suggs received technical fouls. Bitadze was ejected.

Orlando’s Jalen Suggs jumps between teammate Goga Bitadze (right) and Celtics center Kristaps Porzingis (left) in a scuffle in the fourth quarter Monday night. Bitadze was ejected following the sequence, while Suggs and Porzingis got technicals. Julio Aguilar/Getty

“Nothing, just competing, started talking a little bit, and we went face to face and kept on talking and Bitadze came from the side and kind of shoved me, and of course I reacted to that,” Porzingis said, “You could tell how much it meant to them, to win this game. They were really prepared and the way they were celebrating after the game, it’s a compliment to us.”

Similar to their home win over the Celtics just over a year ago in the NBA Cup, the Magic heartily celebrated their victory over the defending champions. Suggs was dancing with the Magic’s mascot after the game as Orlando earned another comeback win after outscoring Miami 37-8 in the fourth quarter Saturday.

The Magic are No. 1 in the NBA in points allowed and fewest 3-pointers attempted per game. Brown, Horford, and Porzingis were a combined 2 for 16 from the 3-point line and the Celtics struggled to even get off clean 3-point looks.

“I thought we passed up a couple in the first half, but I thought that was part of their game plan with their switching and their physicality,” Celtics coach Joe Mazzulla said. “The game calls for the best shot. We have to take those best shots, and when we didn’t turn the ball over, I thought we fought for a pretty good shot.”

The Celtics were just minutes from being fully healthy for the first time in a few weeks, but Tatum never made it onto the floor with his teammates. He was in the locker room pre-game as normal but then was listed as questionable just prior to tipoff. While the Mazzulla and players knew he was unavailable when the game began, the Celtics announced Tatum was out at halftime.

Tatum’s absence allowed Brown to be more aggressive, and he scored 15 first-quarter points as the Celtics jumped to an 11-point lead. Brown added another bucket and Jrue Holiday followed with a steal and score to boost the lead to 58-43 at halftime.

The Magic countered with a 16-6 run to begin the third and suddenly the Celtics were in a street fight and were never able to truly regain the momentum.

“We could have adjusted a little bit earlier,” Porzingis said. “Knowing that there wasn’t a lot of stuff being called and we can also use that (to our advantage). We have to be ready for that offensively, but we can also use that more defensively if it’s that type of game.

“Overall, it’s great to play against a team like this that’s able to have this kind of intensity and physicality in a regular-season game.”

Gary Washburn is a Globe columnist. He can be reached at gary.washburn@globe.com. Follow him @GwashburnGlobe.