Sixers Eastern Conference preview: The Celtics aren't going anywhere

With much of the Sixers' 2024-25 roster locked in more than a month removed from the start of a franchise-altering free agency, the time has come to evaluate their opposition in the Eastern Conference: of last season's playoff teams in the East, which ones pose the biggest threats to the Sixers, and how do the teams match up with this new-look team?

Up first are the Sixers' bitter rivals who won the 2024 NBA Finals: the Boston Celtics.

The 2023-24 NBA season was a dream run for the Boston Celtics. After coming up just short of winning it all time and time again, Celtics President of Basketball Operations Brad Stevens made a slew of risky moves to reshape the team's roster. The result: a 64-18 regular season, a 16-3 record in the playoffs and the team's first NBA title since 2008.

Most championship-winning teams lose core pieces after reaching the pinnacle of the sport. In a league where rosters are limited by a soft salary cap, it is inherently challenging to sustain a championship-caliber group for more than a year at a time. Yet, here the Celtics are, preparing to run it back with every single critical piece of their title-winning rotation in the 2024-25 season.

During the Celtics' run through the Miami Heat, Cleveland Cavaliers, Indiana Pacers and Dallas Mavericks, 10 players logged at least 69 total minutes: Jayson Tatum, Jrue Holiday, Jaylen Brown, Derrick White, Al Horford, Payton Pritchard, Sam Hauser, Kristaps Porziņġis, Luke Kornet and Xavier Tillman.

All 10 of those players are under contract for the Celtics in 2024-25. Horford and Kornet are the only ones not already under contract in 2025-26. Despite the NBA's new, extremely punitive second apron, Stevens has managed to assemble a roster that is both dominant and sustainable, paired with a burgeoning young head coach in Joe Mazzulla who appears to be a perfect fit with the group, both schematically and personally.

Roster changes

Let's take a look at just how little change the NBA's best team experienced this summer:

Added: Baylor Scheierman (No. 30 overall pick in NBA Draft)

Retained: Xavier Tillman, Neemias Queta, Luke Kornet, JD Davison (two-way contract)

Extended: Jayson Tatum (five years, $315 million), Derrick White (four years, $125.9 million), Sam Hauser (four years, $45 million)

Lost: Oshae Brissett, Svi Mykhailiuk

Perhaps the only negative all summer for the Celtics is that team owner Wyc Grousbeck, who has owned the storied franchise since 2002, announced his intention to sell it in the near future. Given the enormity of the luxury tax bills the organization is going to be facing on a yearly basis, it is an understandable decision for an owner who has now presided over two championship teams.

Depth chart projection

Porziņġis is likely going to miss the beginning of the regular season, but is expected to be back early on in 2024-25. He will round out the league's most dangerous lineup, which is supplemented with at least three high-level reserves as well as multiple players with real chances to become quality contributors in the NBA.

The Celtics' rotation figures to be the NBA's best once again:

The most impressive aspect of Boston's roster is obvious: they have a ton of very good basketball players. But on top of that, all of their rotation pieces are multi-positional, all of them have multiple demonstrable skills on offense and nearly every single one also has clear value on the defensive end of the floor. It is a team made up of malleable players who have been put in the absolutely perfect position to be their best selves.

Matching up with the Sixers

The two Eastern Conference contenders who entered this offseason with the ability to make significant upgrades to their rosters -- the Sixers and New York Knicks -- both aimed to make themselves more challenging opponents for Boston in a hypothetical playoff series. It resembles the manner in which teams tried to mirror the Golden State Warriors' success during their dynastic run.

Perhaps the hallmark of Boston's success is their duo of primary franchise cornerstones in Tatum and Brown, two young wings who continue to ascend and have completed the transformation from rising stars to mainstays near the top of the league's hierarchy, before becoming champions last June. Brown is 6-foot-6, Tatum is 6-foot-8, and they have formed what may be the most dangerous wing duo in recent NBA history.

So, teams who want to become serious threats to Boston better make sure they have defensive talent on the wing. That was a primary goal for the Sixers this offseason, and they knocked it out of the park, bringing back their most versatile wing from last year's team in Kelly Oubre Jr. while adding a full-fledged star in Paul George and a reliable two-way player in Caleb Martin who has tormented the Celtics in the past. 

The Sixers' projected starting lineup of Tyrese Maxey, Oubre, George, Martin and Joel Embiid lacks muscle on the interior and may be vulnerable on the glass, but one could argue it was largely designed to contend with the Celtics' dynamic group, and in that capacity, this unit makes a lot of sense. They are certainly not as talented as Boston on either end of the floor, but the Sixers have collected the ideal archetypes of players who could theoretically give the Celtics fits. 

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Looking past the wings, the idea of a series between these two teams becomes especially interesting because Boston's starting lineup presents immense difficulties for one Sixers star while looking potentially vulnerable to the strengths of another. 

Maxey is about as good as it gets as a scorer for a young guard; his top-tier speed and quickness paired with an elite shooting stroke make him nearly impossible to defend. But in Holiday and White, the Celtics have two of the three best defensive players at the guard position in the entire world (shoutout to Alex Caruso). That is even before you get to Brown, who despite being a strong wing is more than capable of defending smaller players -- in fact, that is often where the reigning NBA Finals MVP is actually at his best on the defensive end of the floor. These two teams could play an entire seven-game series against each other and Maxey will never feel an inch of breathing room for one second. 

Meanwhile, the optimized version of Embiid -- meaning one that is at full health -- should be able to score at will against this team, particularly when Porziņġis is in the game. The 7-foot-3 Latvian is an incredible shot-blocker, but lacks the requisite strength to contend with Embiid down low. During the regular season last year, Mazzulla actually gave the Embiid assignment to Holiday -- who is only 6-foot-4 but incredibly strong and absolutely fearless -- until Al Horford checked into the game. 

The only way the Sixers can knock off the Celtics in a playoff series is if Embiid is far and away the best player on the floor. If he can pull that off, he will need George and Maxey to both be near their best selves as well, and at least one of Oubre or Martin will need to get hot from beyond the arc.

The issue is that Embiid has always been capable of dominating the Celtics. But for more than half a decade, it has simply never happened under the brightest of lights. 

So, can the Sixers actually take down their arch enemies this season? It largely hinges on Embiid, and this may end up being the best team they have put together during his career. But the Celtics were far better than ever in 2023-24, and are returning the exact same group. 

You can never say never in the NBA. But the chances of the Sixers -- or any Eastern Conference team, for that matter -- taking down the Celtics remain microscopic. 

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