Who is the player, not named Jayson Tatum or Jaylen Brown, most important to the success of the 2020-21 Boston Celtics?
While our first notion to wonder if anyone is nearly as important as Tatum and Brown for this year’s team, the rather obvious answer here is Kemba Walker. When healthy and playing to his All-Star potential, the Celtics have three potent offensive weapons which forces opponents to pick their poison.
But we wondered if last season's data would back up our assumption. If we submit that Tatum and Brown are now the clear cut focal points of this team then the answer to the original query is whoever brings the most out of that duo while playing alongside them.
With a goal of trying to identify the player that best accentuated the Tatum/Brown tandem last year, we decided to check the on/off data for the primary returning players this season to see what jumped out.
First, as a baseline, the Celtics owned a net rating of plus-9.6 in the 1,267 minutes that Brown and Tatum shared the court last season. Among the 179 2-man units that played at least 1,000 minutes, the Brown/Tatum combo ranked 19th overall, but 10 of the combinations ahead of them were from Milwaukee based on the Bucks' regular-season domination.
Here are Boston’s net ratings for how the Jays performed when each of the following players was on the court with them, versus off, during the regular season:
Your eyes naturally land on the numbers with the Williams duo but it’s a small sample size at play. Grant Williams logged only 181 regular-season minutes next to the Jays; Robert Williams only 75. Daniel Theis is the most surprising because of how much the net rating popped without him and yet he undeniably aided Boston’s starting 5 last year.
Then there’s Walker. It’s notable that the net rating went up a bit without him but it’s hard to quibble with the on-court production when he was out there. Among all three-man lineups with at least the 724 minutes that Tatum, Brown, and Walker logged last season, the trio ranked just outside the top 25 in net rating.
It made us wonder what happened in the postseason. With Walker battling knee soreness, would the numbers plummet? A look at the postseason on/off net ratings for the same players:
Even with Walker hobbled by a balky knee, his presence was critical to the success of the Jays. When Walker was off the court, it allowed defenses to put extra attention on Tatum and Brown, and the team struggled to stay afloat.
Dig deeper into the numbers and that’s really accentuated. Boston’s offensive rating with the Walker/Tatum/Brown trio on the court for 422 minutes in the postseason was a solid 110.5. That number plummeted to an anemic 98.4 in the 122 minutes that Tatum and Brown played without Walker.
All of which only seems to confirm our initial suspicion: Walker is the most important player not named Tatum or Brown for the 2020-21 Celtics.
It’s a reminder of why Boston is treading cautiously with Walker out of the gates. After spending the entirety of calendar year 2020 dealing with knee soreness, the Celtics put him on a 12-week strengthening program aimed at giving him the best chance to feel like his old self.
Walker could miss around a month depending on when the team is comfortable trotting him back out. The Celtics had been operating with the assumption that the NBA season would start around MLK Day (January 18) when they established that plan, which means Walker will miss at least 15 games if he does not return before that date. If his absence lingers into February, he’ll miss at least 21 games.
For his part, Walker has said there is no rush to get back on the floor. As Walker himself noted, "I want to play at a high level in front of the fans who come to watch this game. So I want to be at my best. The last time in the playoffs, I wasn't at my best, and that sucked. I don't want to be that way no more."
The Celtics will weather that absence because, as the data showed, it’s imperative that the team has a healthy Walker for the postseason. Premium seeding won’t matter if Walker isn’t able to stay on the court or play at a high level. He’s gotta get that knee right.
Walker’s absence will be an opportunity for some other candidates for “most important” to state their own case.
With Gordon Hayward gone and Walker sidelined, Marcus Smart will have an even larger role but his focus needs to remain on defense and playmaking. Once he’s recovered from a hamstring strain, we’ll see how offseason addition Tristan Thompson impacts the performance of the Jays.
Grant Williams could sneak into the conversation if he emerges as a starter and maintains numbers anywhere near the small sample from last year’s regular season. We remain convinced Robert Williams could really flourish alongside the Jays if he can earn coach Brad Stevens’ trust on the defensive end.
Ultimately, the ceiling of these Celtics hinges most on Brown and Tatum. If they make another jump after the trampoline-like bounces of last season, then the Celtics are legitimate title contenders regardless of the variance in the performance of the supporting cast.
But a leap from the Jays AND a healthy Walker is undeniably Boston’s best shot at reaching its loftiest goals.