Think back to the first months of the season, when the Boston Celtics dominated offensively and played one of the most aesthetically pleasing styles of basketball in the NBA.
The players cut without the ball. The Rock was often built to be the fastest player on the floor, and the Celtics’ shots weren’t just open; all were in the flow of the offense and designed to punish the defender for trying to help on the perimeter.
Those early games were based on a five-out offensive system (all players positioned around the perimeter) with a rotation of players who could all carry the ball, create for themselves and/or others, score at multiple levels, and create mismatches from the screening action while playing at pace .
Yes, the defense was porous at times, but the Celtics went into every game looking like they could outscore the opposition and played with a swagger that came from an understanding of their talent and depth to match the best the NBA has to offer.
However, since the return of Robert Williams, Boston has reverted to a double-man lineup, where they often run a four-out, one-in design, putting Williams in the dunk spot. In theory, this shouldn’t be a problem. Williams provides vertical spacing and can get out on the perimeter and act as a focal point for the team’s ball movement.
However, by returning Williams to the starting five, Boston gave up one of their ball players, and the balance of their offensive movements had to change. Suddenly, teams could feel comfortable sending a double ball or hard hedge to the receiver, knowing that their low defensive line could rotate to mark Williams’ throw or pick up his layup, and that fluid movement we’ve grown accustomed to slowly began to freeze.
What’s interesting is that of Boston’s five most-used lineups boasting a positive scoring margin, only one of them features a double-double tandem, with a rotation of Derrick White, Jaylen Brown, Jayson Tatum, Al Horford and Robert Williams. and +46 over 138 possessions (just enough to quantify the stat at 100).
Other lineups include either Tatum or Grant Williams at the 4, both of whom aren’t what we’d classify as bigs in the general sense. According to glass cleaning, the lineup of Marcus Smart, White, Brown, Tatum and Horford is the one Mazzulla has used the most, accounting for 662 possessions throughout the season while amassing an impressive +13.2 point differential.
With Robert Williams currently out with an injury, the Celtics have started giving teams more looks at their five-man lineup since earlier this season, and for the most part, we’ve started to see signs of the impact he can have. When you look at how the team performed against Portland Trail Blazers on wednesday night, you could see they penetrated more, chased paint touches and moved without the ball while throwing different looks at the blazers defense.
In the play above, we can see the Celtics go to Derrick White as a reverse screen-toss player, where the guard sets a ball screen to Tatum before sliding into a short throw, engaging the Blazers’ low defense before redirecting the rock to Horford who went unchecked on low post.
Guarding this type of action is incredibly difficult, especially when teams try to shut down a star shooter and the reverse action catches them by surprise. This season, White is converting 65% of his looks around the rim and 44% in the short mid-range (what I call the float area) which ensures that defenses have to step up to challenge him in the paint.
Herein lies the advantage of moving away from twice the size of the line-up. The Celtics, as currently constructed, are a nightmare matchup when they stick with one big man who plays above the perimeter — they can run layups, their fumble series is more fluid, and defenses can’t fool their man, simply put, they’re night again seas for defense and containment.
Of course, if you are facing Joel Embiid, Nikola Jokic or Cleveland Cavaliers world, then by all means throw the two big ones on the floor and make their lives miserable. Still, as we’ve seen so many times this season, there’s value in having multiple decision makers share the field and allow them to operate with a certain amount of autonomy in a read-read system.
Mazzulla started this season with his own style of play, his own system and new offensive principles, but lately it seems like he’s trying to create a hybrid of Ime Udoka’s Celtics and his own, and for the most part it’s been a clumsy mess. Maybe now is the time to go back to what worked the last few weeks of the season and start rebuilding a true identity on the offensive end of the floor before the playoffs begin when every game starts to carry extra weight.