After what felt at times like an 82-game preamble, the Celtics’ pursuit of their second consecutive NBA championship will begin in earnest Sunday at TD Garden.

Boston earned the No. 2 seed in the Eastern Conference by posting a 61-21 record — the best by a defending champ since 2015-16 — and bulldozing through the back half of its schedule, going 29-6 in its final 35 games. Its first-round opponent: the young, tough Orlando Magic, who finished seventh in the East at 41-41 and defeated the Atlanta Hawks in the NBA Play-In Tournament.

Before Game 1 tips off (3:30 p.m. ET, ABC), here’s a breakdown of how these squads match up:

Celtics offense vs. Magic defense

Orlando boasts one of the NBA’s best defenses, trailing only Oklahoma City in defensive rating during the regular season. The Magic’s M.O.: switch, chase opponents off the 3-point line and rely on their top-tier rim protection while wearing teams down with their size and physicality. In addition to their elite defensive rating, they also allowed the fewest 3-point makes and attempts by a wide margin, led the NBA in blocked shots, forced the second-most turnovers and ranked third in fouls committed per 100 possessions.

That makes for a fascinating contrast of styles against a Boston team that shattered the NBA record for made threes this season. Two of the Celtics’ four lowest single-game 3-point attempt totals (33 and 37) came against the Magic, as did their two lowest totals of long-range makes (seven and eight).

“They’re one of the best defenses in the league,” Celtics guard Derrick White said Saturday. “Their numbers speak for themselves, and just their physicality and pressure. I think, especially in Orlando, we had a lot of turnovers. So it’s obviously a big emphasis to take care of the ball and just handle their pressure.”

In the game White mentioned — a 108-104 loss at Orlando just before Christmas — the Celtics were missing Jayson Tatum, and the Magic were without top stars Paolo Banchero and Franz Wagner. In the rematch at TD Garden a month later, Boston was at full strength and blew out the Wagner-less Magic 121-94. When the teams met again in the final week of the season, Orlando had Banchero and Wagner available, but the Celtics rested their entire starting lineup and were spanked 96-76.

So, we have yet to see these teams square off with both at full strength, which adds an element of unpredictability to this series.

Celtics defense vs. Magic offense

The Celtics are elite offensively (second in rating) and defensively (fourth). The Magic aren’t nearly as balanced. Their top-heavy offense boasts two All-Star-caliber centerpieces in Banchero (25.9 points per game) and Wagner (24.2 points) but little reliable production behind them. Orlando ranked 27th in the NBA in offensive rating — only Brooklyn, Charlotte and Washington were lower — and is one of the NBA’s worst shooting teams, with bottom-three marks in true shooting percentage (28th), effective field-goal percentage (29th) and 3-point shooting percentage (30th).

Those struggles applied to Banchero and Wagner, too. Out of 89 players who appeared in 20-plus games and attempted at least 5.5 three per appearance, their hit rate on those shots ranked 81st and 89th, respectively.

One thing Orlando does do effectively is get to the foul line. The Magic ranked 27th in field goals made per 100 possessions but first in free-throw attempts per 100 possessions, drawing more fouls than any other team. That’s another stark dichotomy, as the Celtics committed the second-fewest fouls and sent opponents to the line at the lowest rate in the league.

“I think just being disciplined,” White said. “They’ve got a lot of guys that are attacking, and this has been the case for every series. Just try to be disciplined, try to make them make field goals and not free throws. Obviously, they’ve got really good players that are good at what they do, and so it’s just a concerted effort to just be disciplined.”

Health report

Since they were essentially locked into the No. 2 seed for the final several weeks of the season, the Celtics had the luxury of being able to give all of their key players additional rest ahead of the playoffs. The result: a roster that’s largely injury-free.

The only real health concern for Boston is the status of Jaylen Brown’s right knee, which has pained him since before the All-Star break and kept him out of the final three regular-season games.

Brown was a full participant in practice this week, however, and several teammates shared positive reviews of his performance. He and head coach Joe Mazzulla said he would not have a minutes restriction against Orlando, though it’s unclear whether the knee is 100% healed.

“He looks good,” Mazzulla said. “He was able to do everything, no limitations. He’s been great, physically, mentally, really preparing himself, ready to go. So, love the week that he had.”

The Magic lost starting guard Jalen Suggs and top reserve Moritz Wagner to season-ending injuries — significant losses that diminished Orlando’s depth — but are otherwise healthy.

Celtics X-factor

Kristaps Porzingis. The Magic don’t have a good answer for a 7-foot-2 center who can bang inside and drain 30-footers. Porzingis went 7-for-10 from the field and 3-for-5 from 3-point range in one of his games against Orlando this season, scoring 23 points in a Celtics romp. In the other, he was 2-for-10 but was 13-for-14 from the foul line — five more free throws than he attempted in any game this season. Porzingis also is healthy, having recovered from the lower leg injuries that cost him the first month of the season and most of last year’s playoff run, and the illness that sidelined him for nine games last month.

Magic X-factor

Cole Anthony. Underdog Orlando will need its supporting cast to produce to have any chance in this series, and Anthony has proven he can deliver big scoring nights off the bench. He had one against the Hawks in the play-in (16 points, 4-for-9 from three) and another against the Celtics’ backups a week earlier (18 points, 5-for-10 from three). Whether Anthony can do that consistently, though, is another matter. He scored fewer than 10 points in more than half of his appearances this season, including 22 games with five points or fewer.

Did you know?

The leading scorer in the most recent Celtics-Magic playoff game: Paul Pierce. Boston has faced 14 different teams in the postseason — including every Eastern Conference team except Charlotte and Detroit — since its last matchup with Orlando, which came way back in the 2010 East finals. That also was the last year the Magic won a playoff series.

Prediction

Celtics in five.