X-Factors Making and Breaking Boston Celtics' NBA Championship Case
The Boston Celtics were sitting on top of the Eastern Conference heading into the All-Star game at 42-17. During that time, they removed the interim tag from Joe Mazzulla's title, making him the franchise's official head coach.
Since then, things have slowed notably for Boston, with the team just 10-7 since All-Star Weekend.
On March 28, the Celtics were cooked by the Wizards, 130-111, despite being 11.5-point favorites. But they've also lost to a lowly Rockets team, and they gave up big leads in each game of a three-game losing streak in early March.
For a middling, fringe contender out East, that might sound par for the course. But the Celtics are a top-three seed thirsty for a second straight Finals appearance, all with Giannis Antetokounmpo's Milwaukee Bucks and Joel Embiid's Philadelphia 76ers standing in the way.
Boston and Milwaukee face off in a potential Eastern Conference Finals preview Thursday night on TNT.
Questions and criticisms about Mazzulla's coaching tactics are fair—expected, even, for a first-year leader in charge of turning Finals runner-ups into world champions.
As the regular season wraps and the postseason nears, specific aspects of Mazzulla's game plan have turned into the biggest X-factors for the Celtics as they make another run at the Finals.
The following three subcategories are the ones that can make all the difference.
End-of-Game Creativity
One area a coach can have a heavy, tangible impact is at the end of a close game.
The Celtics have been a bad clutch team in recent years. To be fair, this season they have been better than last year. Under Ime Udoka in the 2021-22 campaign, the Celtics had a net rating in clutch games of -9.5, per NBA.com. Now, under Mazzulla, it has improved drastically, with a clutch net rating of 8.0.
However, recent trends matter. After the All-Star break, Boston's clutch rating has dropped in their nine clutch games to -5.5. Before then, their clutch rating was 13.7 over 26 games. That is a full 19.2-point swing.
One thing that has stood out after the All-Star game is how little creativity Mazzulla has had at the end of games. He has used the same three-play several times.
The play worked perfectly in a win against the Philadelphia 76ers.
Jayson Tatum starts in the backcourt. Marcus Smart flashes to near half court to catch the inbound pass as Tatum runs off him, putting the defense on its heels. Tatum drills a game-winning three-pointer.
An important scouting note: Teams pay special attention to what opponents run at the end of games. Some keep a file of the end-of-game plays every team runs. Video rooms put together an edit of the final two minutes of games (including overtime).
The moment Boston ran this, every team updated their end-of-game files.
Mazzulla pulled out this play against the Jazz two weeks later, and Utah was prepared. It also did not help that Will Hardy, a former Celtics' assistant coach, now coaches the Jazz.
Either way, the end result was Markkanen denying the catch to Grant Williams, who then caught the ball and tried to take it to the basket but was blocked by Walker Kessler.
Wedged in between these games was a double-overtime loss to the Knicks. The last play of the game, the Celtics ran a similar action, but not the same one.
This time, Tatum caught the ball in the backcourt and came off a high pick-and-roll. He dished it out to Al Horford for the three, but the veteran was unsuccessful.
The Celtics are also 5-7 in games decided by three-points or fewer.
Mazzulla needs to change up his end-of-game plays because teams are watching.
Rotation Issues
Mazzulla needs to figure out playing the right guys at the right times. To be fair to the first-year head coach, he's dealt with injuries and load-management issues that have made creating the rotation challenging.
That said, there is not much of an explanation for why Derrick White's fourth-quarter and overtime minutes haven't been consistent.
Chris Forsberg of NBC Sports Boston tweeted out the details. White has played only 16.3 overtime minutes of Boston's 60 minutes available.
It should be noted that Boston is 4-7 in overtime, and that this tweet came after White logged zero minutes in the fourth quarter against the Jazz when they blew a lead.
It's fair to start with the question: Why should White play more in the fourth and overtime?
For starters, the Celtics have a 10.6 net rating with White on the floor and a 0.5 rating when he's off, per NBA.com. That is the biggest swing of anyone on the roster. It is better than Smart, Williams or Malcolm Brogdon's on/off numbers. Yet all three are averaging more fourth-quarter minutes than White.
Looking at five-man lineup data, over the 10 most used lineups the Celtics have used, White is on six of them—all of them have a positive net rating.
These lineups range from playing small-ball lineups and two-bigs lineups, proving White needs to be considered a core player for the Celtics in key moments, especially in crunch time.
Timeout Questions
Timeout usage has been one of the most consistent complaints of Mazzulla this year, even before the Celtics' swoon.
Mazzulla simply does not call timeouts often, even when the team is struggling. Case in point, in that loss to the Knicks, New York ripped off a 10-2 run before Boston called a timeout.
This is not a new concept. Phil Jackson was known to not call a timeout when it looked like his team needed one. His philosophy was they need to work on getting out of these issues on their own.
It is not clear if Mazzulla subscribes to that Jackson timeout philosophy. The next game after the Knicks, the Cavs went on a 4-0 run to start the half, and Mazzulla called a timeout to stop the run. Immediately.
For those unaware, there are mandatory timeout windows in the NBA for commercial breaks at the seven- and three-minute marks of games. Once there is a dead ball after those marks, a timeout will be called and charged to a team.
The Celtics are the only team to have more than half of their timeouts (51.7 percent) come during those windows, according to data Seth Partnow shared with Bleacher Report. The next closest team is the Phoenix Suns at 44.8 percent.
This shows the hesitancy from Mazzulla to call timeouts to stop runs, and it appears at times as if he's almost going along with the media timeouts.
But more important than the timeouts to stop runs are the timeouts at the end of games. Going back to the Utah loss, with two timeouts in the final three minutes, the Celtics used their first one with 35.5 seconds left in the game and down one.
It's not surprising that Tatum starts the play in the backcourt. What was surprising was the play-call: a rushed three-point attempt to go two-for-one in this situation. I'm not sure a timeout was necessary to get a quick shot.
The next time is the Williams play shown below. Had they saved that first timeout, Brogdon could have called a timeout once Williams was denied by Markkanen and ran a new play.
There is plenty to like about Mazzulla as a coach. The most important thing is that the players play for him. He was also thrust into an extremely difficult position that most first-year coaches never experience, earning the job after Udoka's suspension Sept. 22 and with training camp starting Sept. 28.
Most head coaches have an entire offseason to prepare for the season. Mazzulla had six days.
That's a tough position to put anyone in, especially a first-year leader. Mazzulla is a good coach and has an incredibly bright future. He does need to change up his end-of-game play-calling, tweak his rotation and use his timeouts wisely in the playoffs.
The postseason is when coaches can have the most impact on a game—and a series—and that's when Mazzulla can swing the Celtics' X-factors in their favor when it matters most.
*Mo Dakhil spent six years with the Los Angeles Clippers and two years with the San Antonio Spurs as a video coordinator, as well as three years with the Australian men's national team. Follow him on Twitter, @MoDakhil_NBA.
