Udoka becomes just the third Boston coach in the past 17 years.
As much attention was put elsewhere, a fundamental reason Boston declined by 12 wins from 2019-20 to 2020-21 was the team’s defense with key players on the court.
Despite injuries, that group actually played slightly more possessions together this season and dropped to the 2nd percentile on defense.
Still, that’s notable because Boston had been such an incredible outlier in terms of how poorly opponents shoot 3s against them.
Across the tenures of both Rivers and Stevens, the Celtics had ranked in the bottom 10 in opponent 3-point percentage every season between 2007-08 and 2019-20, posting the lowest mark in the league three times and the second-lowest three others.
Horford gives Boston another versatile defender at center as well as an alternative at power forward against bigger opposing frontcourts.
Even if the Celtics can’t rediscover whatever they were doing differently from opponents to contest 3-pointers — or if their streak was more about random chance than gaming the system — their defense should benefit from the pull of regression on open shooters.
Two of the three teams behind the Celtics, the Dallas Mavericks and Portland Trail Blazers, were among the league’s top eight in offensive rating.
According to Second Spectrum tracking data on NBA Advanced Stats, Boston was far more elite when it came to shots with less than two seconds of touch time — typically shots off assists.
So it’s a concern that just two teams took a higher percentage of their shots after at least two seconds of touch time than Boston’s 53%.
The Nets were able to leverage the attention paid to Kevin Durant, James Harden and Kyrie Irving to create opportunities for their less-heralded teammates.
Point guard Payton Pritchard averaged 19 MPG as a rookie, solidifying the backup spot, while Robert Williams III moved into the starting lineup after the Celtics traded starting center Daniel Theis at the deadline, and Grant Williams was one of Stevens’ most trusted reserves.
As Boston starts to make decisions on some of these players, the urgency for them to develop accelerates.