We’re mere weeks away from a new NBA season, and a pretty anticipated campaign by the Boston Celtics. As we’ve discussed all summer, the new CBA has made Boston’s championship window very heavy, and it threatens to slam shut a lot earlier than originally expected.
The team acknowledged as much with their moves this summer, deciding to make a big change to the roster and lean heavily into Joe Mazzulla’s style of basketball. However they do it, they have to make this thing work, and do so quickly.
Here’s a quick look at five stats that Boston will have to change this upcoming season in order to succeed and realize their championship aspirations.
Free throw attempt rate: .243, 27th NBA
The Celtics are going to be a 3-point heavy team under Mazzulla, but that doesn’t mean they forget about drives. The hierarchy of desired shots in the NBA is (1) open layups, (2) free throws, and (3) 3-pointers.
Boston needs to remember this hierarchy and understand how important it is to pile up points at the free throw line. I think one lesson the Celtics can take from the Conference Finals is that a healthier free throw rate (and free throw percentage) could have helped them avoid a 3-0 hole against Miami and maybe win that series in less than seven games.
Their free throw rate was .265 against Miami, netting them 22 attempts per game in the series (they shot 79.2%). Even though the story of that series was the outrageous outlier shooting by Miami and Boston’s complete meltdown from beyond the arc, a stronger driving Boston team could have picked up four more free throws per game at their regular season free throw percentage of 81.2%, they would have picked up 3.7 points in a series where the point differential was -3.9
I know that's not exactly how it works, but the point stands. A free throw attempt rate at the bottom of the league put too much pressure on the shooting to win games. And I honestly don’t care about the overall number of 3-point attempts if there are enough drives and attempts at the rim to put Boston on the free throw line to start stacking up free points.
Side note: There is a distinction between open layups and contested layups, and the numbers show that an open corner 3-pointer can be a more efficient shot than a contested layup. That's why you see guys starting to pass out of those more often and why we have talked so much about rim-reads being so important. Making the wrong rim read and taking a contested layup versus an open corner 3, or passing out of a clean layup attempt for a lower percentage shot, can hurt.
Opponent turnover rate: 12.6, 26th NBA
This is tied to the lack of free throws since so many fouls are drawn after turnovers when a team is in transition.
Boston has to get their opponents to cough it up and get out into transition to start stacking easy points. Once again, this serves as a backup plan for when the shooting betrays them. If the Celtics can rely on other ways to score and keep their confidence up while the long-range bombs aren’t falling, they can get past slumps a little more easily.
This isn’t really rocket science. And while Boston’s best perimeter defender is gone, the arrival of Kristaps Porzingis to pair with Robert Williams on the back line could empower perimeter defenders to take an extra chance or two knowing there are two elite rim defenders behind them.
The Celtics can also toss in some zone coverage to help protect the rim some more and maybe pick off an errant pass or two. However they play it, they could simply make it a priority to take a few more risks defensively knowing they have help behind them.
And, to be fair, not having Robert Williams for half of last season probably played into the lower opponent turnover rate for this very same reason. The emphasis was less on forcing turnovers and more on trying to stay disciplined in rotations. If everyone is healthy, the directive from the coaching staff could be to take the risk rather than avoid it because the risk is mitigated by the rim protectors while the reward of transition buckets and fouls is still pretty high.
Pace: 99.15, 20th NBA
This is all part of the pattern.
Get more free throws. How? Force more turnovers.
What do you get when you force more turnovers? Increased pace.
Pace is the measure of possession per 48 minutes, so the higher the number, the more possessions a team gets. Teams pump that number up by getting steals, rebounding on both ends (ending the other team’s possession quickly and then tacking on more with some offensive rebounds of their own), and getting good shots early in the shot clock (more on that in a second).
Is pace alone a direct indicator of winning? No, not necessarily. Half of the top 10 in pace last season had losing records. But there's no reason for Boston to be in the bottom third of this category either.
The Celtics have to win the possession battle in order to get the volume of shots they want. They are a 3-point-reliant team whose two best players were 111th (Jayson Tatum) and 131st (Jaylen Brown) in 3-point shooting. Al Horford and Malcolm Brogdon were in the top five while Sam Hauser was 13th, but they don’t get enough shots consistently enough to buoy the shooting numbers when Tatum and Brown are struggling.
Boston needs to win the possession battle in order to get their stars the number of shots they need to get going, so even if they are hitting an average number of shots, the numbers still work out in their favor.
Cut frequency: 5.7, T-23rd NBA
This is just me continuing to die on the “Will they please just cut more?” hill. Don’t mind me. Cutting just decimates defenses, leading to easy buckets and fouls, but what do I know?
Unfortunately, the five-out spacing seems to be more of an invitation to hunt mismatches and go one-on-one than it is a chance to send cutters into the space, cause overreactions, and then react to those with good looks and easy buckets.
This is where those early shot clock opportunities manifest themselves the most. Clearing a rebound, pushing the pace to force cross-matches, and then cutting when opponents might be trying to scramble and switch can lead to layups and dunks. Frankly, this might be where Boston misses Marcus Smart the most. He and Brown nailed teams on baseline cuts once a game. No one else hit Brown with that pass.
My hope is that Robert Williams can serve as a high post passer to wing cutters for easy buckets. I can close my eyes and see Williams faking a handoff to one guy curling over the top and then spinning to hit a cutter for a layup.
The cuts are there more than 5.7% of the time. Take those opportunities when they're there and you’ll be surprised at how it opens up some cleaner looks from outside as defenses worry about one extra element of the offense.
Jayson Tatum isolation points per possession: 0.93, T-109th NBA
And to end this string of related stats, this is the one that needs to stop ASAP.
Tatum needs to either become elite as an iso guy or stop isolating.
Of all the players who isolate 17% of the time or more, five players have points per possession numbers lower than 1.0:
Russell Westbrook: 0.77
Anthony Edwards: 0.93
Tatum: 0.93
Julius Randle: 0.97
Spencer Dinwiddie: 0.99
Let’s just chew on the fact that Randle was better at isolating than Tatum last season. That should be embarrassing to Tatum.
I’ve talked about this ad nauseam. Tatum has historically been a bad isolation player, and if the Celtics spread offense is going to lead to him taking over possessions just trying to break down a lesser defender, then he’s going to face the same issues he’s always faced.
However, if he makes quick decisions, plays off two feet, gets to the rim, and finishes through contact, then this number will vault to the top of the list.
One of the things that makes elite players what they are is their ability to make tough plays … or what would be considered bad plays for the rest of us. If Tatum can get to that level, then iso away. But if he can’t, then he needs to scrap this and focus more on getting his transition baskets or cutting more to pump up his scoring.