Here’s the hard fact: the starting lineup of Marcus Smart, Jaylen Brown, Jayson Tatum, Al Horford, and Robert Williams just hasn’t been good this season and that’s putting it kindly. They’ve been pretty bad. The same fivesome that racked up a ridiculous 24.6 net rating (118.8 offensive, 94.2 defensive through 443 minutes) last year is a -12.4 (106.7 offensive, 119.0 defensive through 81 minutes).
Part of it can be chalked up to Robert Williams’ late start to the season. After missing the first 29 games of the season and another eleven to get reinserted into and reacquainted with the starting lineup, Williams still doesn’t look like himself at Game #64. There have certainly been moments when he’s been a wild card in so many wins this season, but that’s just it. A year ago, there was a sense you could expect the unexpected, those 2-3 plays a night where Williams would singlehandedly change the momentum of a game or add the exclamation point to a win.
That’s not to say he hasn’t been effective. After MVP candidate Jayson Tatum and analytics darling Derrick White, he’s third on the team in plus-minus at +4.4. Unfortunately, something’s not working.
One angle of interpretation is that Boston’s double-big lineup isn’t in line with their current identity. With an emphasis on three-point shooting on offense and switching everything on defense, their most effective lineups have been small, featuring either Derrick White in the back court or Grant Williams in the front court.
Celtics Three Most Used Lineups
| Lineup | Minutes | Net Rating | Offensive Rating | Defensive Rating |
|---|---|---|---|---|
| Lineup | Minutes | Net Rating | Offensive Rating | Defensive Rating |
| A. Horford – M. Smart – J. Brown – J. Tatum – D. White | 287 | 13 | 120 | 106.9 |
| A. Horford – M. Smart – J. Brown – J. Tatum – G. Williams | 155 | 2.1 | 111.7 | 109.6 |
| A. Horford – J. Brown – J. Tatum – D. White – G. Williams | 106 | 7.6 | 112.6 | 105 |
And it’s not as if head coach Joe Mazzulla (or Ime Udoka last season) has relied heavily on the Horford-Williams pairing. Last season, Horford and Williams averaged 14.9 minutes a night together last season. That’s down slightly to 12.4 minutes through 24 games this season. The Celtics might start big to open the game and the third quarter but move away from it fairly quickly.
The proof in the pudding might be in not who starts, but who finishes. Despite their recent struggles to hold leads, Boston has the second highest win percentage in the league in clutch situations (72.4%, 21-8) and they’ve been winning those games going small.
Most Used Celtics Lineups in the 4th Quarter
| Lineup | Minutes | Net Rating | Offensive Rating | Defensive Rating |
|---|---|---|---|---|
| Lineup | Minutes | Net Rating | Offensive Rating | Defensive Rating |
| A. Horford – M. Smart – J. Brown – J. Tatum – G. Williams | 59 | 24.6 | 129.4 | 104.8 |
| A. Horford – M. Smart – J. Brown – M. Brogdon – J. Tatum | 29 | -16.8 | 90.8 | 107.6 |
| A. Horford – M. Smart – J. Brown – J. Tatum – D. White | 25 | 35.2 | 124.5 | 89.3 |
| M. Smart – J. Brown – J. Tatum – D. White – G. Williams | 21 | 19.1 | 119.1 | 100 |
| A. Horford – J. Brown – J. Tatum – D. White – G. Williams | 20 | -13 | 119.4 | 132.4 |
There are, of course, the looming matchups with the current #1 seeds in both conferences, the Milwaukee Bucks and Denver Nuggets. Both teams start monster starting lineups that could certainly require beefed up front courts come the playoffs. But that’s a chess match for April, May, and June. To regain their regular season mojo and home court advantage throughout the postseason, the Celtics should consider not just starting small, but playing small as much as possible from here on out.
It’s hard to ignore the roster construction of this team and the analytical philosophy of its head coach. “The three-point attempt rate is the most important stat in the game of basketball because of the pace of play, because of the shot selection, and because of the ability to go on runs,” Mazzulla said after the Nets mounted a 28-point comeback on Friday night.
With Robert Williams out tonight with a left hamstring strain against the Knicks, expect to see the Celtics to go small again — if not exclusively — shooting a ton of threes and aggressively switching everything on the perimeter. Because if Mazzulla is truly a believer in the analytics, it’s all in the numbers.
