Jayson Tatum and Marcus Smart led Boston to the NBA Finals last season.

It wasn’t long ago that some wondered if the Boston Celtics’ coach (Brad Stevens at the time) was more valuable than an All-Star. Well, the Celtics might now help us determine just how valuable a coach can be in today’s NBA.

Ime Udoka had a terrific first season as a head coach, withstanding a 25-25 start, guiding what turned into a dominant team over the last 10 weeks of the regular season, and then pushing the Celtics to the Finals. But with Udoka being suspended for the season, the Eastern Conference champs are in the hands of Joe Mazzulla, a 34-year-old with minimal NBA or head coaching experience.

Everything was looking good for the Celtics to hit the ground running this season. They were returning the top eight players from their playoff rotation and adding another ball-handler – Malcolm Brogdon – who would directly address their weaknesses. With Brogdon on board, eight of their top nine guys are under the age of 30, and all of them can contribute on both ends of the floor. Jayson Tatum (who’s already played in more playoff games than Allen Iverson did) is still just 24 and primed to continue his ascent toward MVP candidacy.

But just as training camp was set to open, Robert Williams III had (another) knee surgery that will keep him out for at least the first month of the season. And then Udoka was suspended, seemingly throwing the franchise into turmoil. This team could still be better than it was last season, but it may once again need to overcome some early-season issues.

BIGGEST QUESTION

Can they execute down the stretch? The Celtics had a 2-1 lead in the Finals and led by four with less than five minutes left in Game 4. But they scored just three points on their final eight possessions of the game, and then scored less than a point per possession as they dropped Games 5 and 6. Clutch offense was an issue all season for the Celtics, who scored less than a point per clutch possession in the regular season and just 57 points on 64 clutch possessions (89.1 per 100) in the playoffs. Another ball-handler (Brogdon) should help, but Brown and Tatum also need to prove that they can come up big on big possessions.

SEASON PREDICTION

Even with the last-minute coaching change, the Celtics should be on the same page more than they were at the start of last season. We can also expect them to be better in close games this year. But we can’t expect them to ever be as dominant as they were over the last 32 games of ’21-22, when they ranked first on both ends of the floor and outscored their opponents by 14.8 points per 100 possessions. There’s no doubt that they’re one of the three best teams in the Eastern Conference, but their ultimate level of success could be determined by Williams’ health and Mazzulla’s ability to steer the ship. Projection: Playoffs.

1 KEY STAT TO KNOW

0.80 — 8.9% of the Celtics’ opponents’ possessions, the league’s highest opponent rate, were isolation possessions, according to Synergy tracking. And they allowed a league-low 0.80 points per possession on isolations.

PROJECTED STARTING FIVE

Marcus Smart: Remains an erratic shooter, but his effective field goal percentage topped 50% for the second time in his career last season.

Jaylen Brown: Playmaking has improved, but turnover issues in the playoffs were evidence that his decision-making could still get better.

Jayson Tatum: May have run out of gas in the Finals, but 25.6 points, 6.7 rebounds and 6.2 assists over 24 playoff games is big time.

Al Horford: 36 and entering year 16, but coming off a couple of big games In the Finals. Provides defense and floor spacing at the 4 or 5.

Robert Williams III: Smart is the DPOY and Horford is the vet, but Williams’ mobility remains the biggest key to the league’s No. 1 defense.

KEY RESERVES

Malcolm Brogdon: Ranked fourth with 18.3 drives per game last season and will take some of the playmaking burden off Tatum and Brown.

Payton Pritchard: Not much defense or offense off the dribble, but 40% 3-point shooting makes defenses pay for the attention paid to the stars.

Derrick White: His minutes in the Finals were rough, but he’s solid on both ends of the floor and you can do much worse for a seventh or eighth man.

Grant Williams: Much improved over his three years in the league, still just 23 years old, and eligible for an extension before the start of the season.

LAST 5 SEASONS

How the Celtics have fared stats-wise over the last 5 seasons …

Last 5 seasons

OffRtg = Points scored per 100 possessions
DefRtg = Points allowed per 100 possessions
NetRtg = Point differential per 100 possessions

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John Schuhmann is a senior stats analyst for NBA.com. You can e-mail him here, find his archive here and follow him on Twitter.

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