Analysis: A closer look inside the Celtics' new glaring issue on defense

On paper, the Celtics still (somehow) have the fifth-best defense in the NBA. There’s no denying there are some serious underlying issues with this group in the wake of giving up the most points as a franchise since 1994 in a 140-115 loss to the Clippers.

Pick-and-roll defense has been a problem all year long, particularly against speedy guards, but a new issue has risen to the surface in recent weeks that has caused a defensive turndown: Giving up easy points in transition.

On the year, Boston has been a middle of the pack team in this department, allowing just 13.4 fastbreak points per game (14th in NBA). However, that average has skyrocketed since the All-Star Break as the C’s have faced a host of opponents that like to push the ball in transition. In the 10 games since February 21st, Boston has allowed 21.2 points per game in transition, which ranks 29th in the NBA, just ahead of the Grizzlies over that stretch. The 21.2 mark is five points worse than the PPG average for the worst transition defense in the NBA this year (Atlanta), showing just how egregious a dropoff that mark is over a 10-game stretch.

Defending the fast break has popped up as a problem early and often on the West Coast trip as well (21.8 fast break points allowed per game), showing that it’s not a problem that was solved by the magic of the team’s "plane ride" and coming together more as a team. Put simply, the Celtics aren’t getting back and matched up quickly enough and that’s producing plenty of easy points for opponents.

What exactly causes bad transition defense? Plenty of missed jump shots (Celtics are shooting 32.6 percent since the Break) is certainly a factor since long misses open the door for opportunities the other way on long rebounds. Making poor decisions on when to attack the offensive glass and just a simple failure to hustle and talk in transition are all reasons for the rise as well for Boston. Let's explore a few common causes on video last month to highlight the regular causes in action. 

Rozier’s gamble on the offensive glass here leads to a 5-on-4 situation in which Morris doesn’t pick up right man running free towards hoop (bad awareness).



A similar situation happens here. Gordon Hayward goes for an offensive rebound and no one covers his man while he gets back. By the time he recovers, it’s too late to contest the 3.



Miscommunication here by Smart and Theis (Smart called for a switch while Theis was engaged in pick-and-roll defense) allowed for an uncontested Zubac layup before Hayward comes over for the foul.



Bad shots have been leading to easy breaks the other way too, along with selfish mindsets by players while they get back. This is a 3-on-4 situation here yet Harrell gets a wide-open look since Jaylen Brown and Marcus Morris are more worried about picking up their other men instead of covering the more dangerous threat (Harrell) once Horford makes the right play (stopping the ball).



With the Celtics having a chance to put together a rare practice on Wednesday, stopping these opportunities proved to be a primary focus for Brad Stevens during the hour-long session.

“I do think we need to clean some things up,” Stevens said. “We talked today about how we have to be much better in transition, and we need to clean up some of our defensive and offensive habits. That’s really the focus of the next month. And so, today, we did a ton of simulation of transition without the sprinting and getting back and guarding actions that we’re going to see a lot of.”

Due to these struggles, the Celtics have simply been a middle-of-the-road defensive team (16th in NBA) since the All-Star Break and that’s not going to get the job done against the offensive firepower among the top East playoff teams. Stevens knows consistent defense is a necessity for this group to play to its potential in the postseason.

“Better transition defense and improve our habits in the halfcourt defensively,” Stevens said of goals for the final 14 regular season games. “Improve our habits in our execution. It’s pretty simple. As you go through the film there are a million things you could highlight. But I think ultimately if we do those three things then we’ll be better than we are today. And I think we need to be better than we are today to be able to move on once the playoff start, regardless of where we’re seeded.”

Like several other aspects of this team’s game, this is an area that Stevens has been harping on for months to improve. A team that is not playing hard or is not fully connected tends to get exposed. The Celtics have a bunch of bigs on the slower sides (Horford, Baynes, Theis) in terms of foot speed and have wings that tend to drift on defense (Tatum, Brown, Morris). The end of result of that is the ugly defense we’ve seen for the past month. The game slows down in the playoffs but this is an area that will leave Boston susceptible against quicker teams if they don’t clean things up now.

A matchup with the No. 1 transition offense in the NBA (the Kings) on Thursday night will prove to be a good test for the first game since focusing on in practice. A lack of improvement on Thursday could signal that this is a problem that is tied more to personnel than to effort/focus. Stevens has to hope its the latter.