The Celtics rallied late against the undermanned Magic but a frantic comeback fell short Monday night with a 108-104 loss at Amway Arena.

Jayson Tatum was a last minute scratch for Boston just moments before tip due to illness. Al Horford got the start in his place but the visitors missed Tatum’s offense for much of the night.

The Celtics were able to build a 15-point lead at halftime largely thanks to their defense but that advantage evaporated in the third quarter. Orlando got red-hot with their shot in the frame, knocking down 60 percent of their attempts and all seven of their free throws as they erased Boston’s lead entirely.

Boston’s offense also went sideways in the third, knocking down just 26.3 percent of their attempts but they managed to stay afloat offensively at the free throw line.

Ultimately, Boston’s offense came to a screeching halt in the fourth quarter as the Magic opened the frame with a 7-0 run and limited the Celtics to one of their worst shooting nights of the season from 3-point range. Orlando pushed their lead to as many as 10 points with 3:36 remaining in the fourth quarter but the Celtics fought back with a 12-1 run to give themselves multiple chances to take the lead in the final minute following the ejection of Goga Bitadze. Ultimately misses from Horford and Jaylen Brown late along with a dagger 3 from Tristan da Silva helped seal the win for the hosts.

Da Silva (18 points) and Jalen Suggs (16 points) led the undermanned Magic who played without their two stars in Paolo Banchero and Franz Wagner. Jaylen Brown had a game-high 35 points for Boston.

The Celtics return to action on Christmas, hosting the 76ers at TD Garden.

Here are four Celtics takeaways from Monday’s loss to the Magic:

Refs allow a physical slugfest: The Magic have one of the best defenses in the league and they knew they would need to play with an extra level of physicality without their top scorers against the defending champions. The end result was arguably the most physical games the Celtics played all season. Orlando made Boston fight for every inch of their offensive movements all night long with steady ball pressure on the perimeter and in the paint. Boston struggled to create all night offensively for themselves, mustering just 24 percent shooting from 3-point range and 13 assists. With limited ball movement on offense, easy looks were hard to come by. The Celtics got to the free throw line a healthy amount but they piled up turnovers (19) that led to a subpar offensive night overall against a feisty Magic squad.

Celtics post a season-low in assists: The Magic’s defense deserves some credit for this but the Celtics did not rely on their offensive principles from a ball movement perspective all night long. They posted a season-low with 13 assists on 37 made field goals, which was four fewer than their previous mark this year. Boston’s offense completely fell apart on this front in the third quarter when they had one assist in the entire frame, clearly missing the presence of Jayson Tatum in helping them break down defenses. White and Brown both had four assists but the entire rest of the roster combined for five as isolation sequences that led to missed shot attempts were far too often.

Celtics can’t find the openings for 3-point attempts: Few teams have the personnel required to take away open 3-point looks for Boston but the Magic were that team all night long. The Celtics didn’t just have a miserable night shooting the ball (24.2 percent from 3-point range) but they couldn’t get up perimeter looks at the rate Joe Mazzulla likes. Boston’s 33 3-point attempts were a season low by a long shot (previous low was 41). The Magic were able to switch well and get over screens all night long, taking away the wide open looks the Celtics routinely creates against most opponents. This night, those attempts went away for the most part with Tatum sidelined and Boston’s offense suffered because of it.

Mazzulla rides the starters hard: Without Tatum available and the Celtics facing a fourth quarter deficit, Mazzulla went back to his starting five for a longer stretch than usual in the final frame. The net result was a season-high in minutes for Porzingis (37) and a big minutes load for Al Horford (35) while filling in. The decision nearly paid off late as the Celtics used a 12-1 run to give themselves a chance in the final minute but Horford missed an open 3-point attempt while Brown rushed a 3-point shot on the ensuing possession that ended Boston’s chances. There have ben few tight situations like this all year long that Boston has fallen short in but it was intriguing to see how they handled one without Tatum in the fold. Brown played well much of the night but the miscues by Boston’s main ball handlers (15 combined turnovers) was ultimately too much to overcome for the visitors.