The Celtics Won’t Have Inexperience to Blame if They Don’t Win This Year

Last week, Mazzulla had the interim tag removed from his title. He had been thrust into the role right before training camp when last year’s coach, Ime Udoka, was suspended for unspecified violations of team policies. The suspension came as a shock since the Celtics were an ascendant franchise coming off a finals run in a league where continuity is at a premium. Almost as surprising was that Brad Stevens, the team’s president of basketball operations and Udoka’s predecessor, handed the keys to Mazzulla, who had been a Celtics assistant for three years but never an N.B.A. head coach.

All Mazzulla had to do was lead the Celtics to a championship. No training wheels. No emotional victories. Just victories.

His presence created an odd and unusual dynamic. For much of the season, Udoka was still technically slated to come back in 2023-24 regardless of how Mazzulla did. But Mazzulla got the Celtics off to a blistering 18-4 start, quieting questions about whether his lack of experience would hinder an elite team. Eventually, the Celtics rewarded Mazzulla with what might be considered gold in N.B.A. coaching: security.

“The East is terrific. Obviously, the West is loaded up,” Stevens said on a conference call last week. “It’s going to be really hard to win.” He added that it would be hard to coach while “looking behind you and looking over your shoulder.”

Mazzulla may not be looking over his shoulder anymore, but the Celtics should be because teams are gaining on them. Since the hot start, the team has looked merely above average at 23-13, rather than world beating. They’re now only a half-game ahead of the Milwaukee Bucks (41-17) for the N.B.A.’s best record and the East’s top seed. Mazzulla has been criticized for not calling timeouts at crucial junctures in games. Over the last 15 games, the Celtics have had a below average offense. During the 18-4 stretch to start the season, the Celtics had not just the best offense in the N.B.A., but one of the best offenses in league history. The good news for Boston is that its defense has steadily improved while its offense has declined.