Coach Nick & Celtics defensive woes

[slightly biased bias fan]

Coach Nick from Bball Breakdown recently came on Celtics beat and gave a stat about why our defence has been so poor this season and it is worrisome, with our best defensive line up (plus Thomas) we have a 129.4 defensive rating but if you remove Thomas (4 man line up) 103.4 defensive rating.

Nick does also says it is not for a lack of trying on Thomas's part but we have a major issues here.

[hpantazo]

I don't know what it is exactly, but we definitely have a problem here. Defense was our calling card last season, and we are terrible at it this season. It seems like we give up 55-60 point halves on a regular basis.

We only changed personnel slightly. We swapped Sullinger for Horford and Rozier/Green for Turner. Why that results in such poor defense I have no idea, but so far it does.

I was hoping it was just a matter of getting everyone healthy and in synch, as we were using Brown and Rozier too much early on, and they didnt have the experience to stick with our defensive rotations, but once everyone was back and clicking, our defense still sucks.

We are certainly active on D, Horford has been making some great blocks and rotates well from what I can tell, Smart has been all over the place getting steals and loose balls. Why are we so bad overall then? Why do we give up 60 point halves to basically any team in the league?

[BitterJim]

I don't know what it is exactly, but we definitely have a problem here. Defense was our calling card last season, and we are terrible at it this season. It seems like we give up 55-60 point halves on a regular basis.

We only changed personnel slightly. We swapped Sullinger for Horford and Rozier/Green for Turner. Why that results in such poor defense I have no idea, but so far it does.

I was hoping it was just a matter of getting everyone healthy and in synch, as we were using Brown and Rozier too much early on, and they didnt have the experience to stick with our defensive rotations, but once everyone was back and clicking, our defense still sucks.

We are certainly active on D, Horford has been making some great blocks and rotates well from what I can tell, Smart has been all over the place getting steals and loose balls. Why are we so bad overall then? Why do we give up 60 point halves to basically any team in the league?

For one, our rebounding is awful, and for another, Amir has slowed down a lot.  Last year, he was covering stretch bigs with Sully playing inside, but this year he's too slow and ends up playing D in the paint more, which leaves Horford on the perimeter playing D (which is bad).  Starting Jerebko (or maybe even Kelly) would help solve that

[Roy H.]

I'm not sure this type of analysis holds up.

For instance, if you look at the 3-man lineup of Horford, Crowder and Amir, the defense gets better if you add IT as the 4th guy as opposed to Bradley.  Does that mean IT is a better defender than Bradley?

Just because somebody uses advanced stats doesn't mean they're using them correctly.  Plus, DRtg is a flawed statistic to begin with. For instance, it tells us that Marcus Smart is a worse defender than Tyler Zeller.

[jpotter33]

I don't know what it is exactly, but we definitely have a problem here. Defense was our calling card last season, and we are terrible at it this season. It seems like we give up 55-60 point halves on a regular basis.

We only changed personnel slightly. We swapped Sullinger for Horford and Rozier/Green for Turner. Why that results in such poor defense I have no idea, but so far it does.

I was hoping it was just a matter of getting everyone healthy and in synch, as we were using Brown and Rozier too much early on, and they didnt have the experience to stick with our defensive rotations, but once everyone was back and clicking, our defense still sucks.

We are certainly active on D, Horford has been making some great blocks and rotates well from what I can tell, Smart has been all over the place getting steals and loose balls. Why are we so bad overall then? Why do we give up 60 point halves to basically any team in the league?

For one, our rebounding is awful, and for another, Amir has slowed down a lot.  Last year, he was covering stretch bigs with Sully playing inside, but this year he's too slow and ends up playing D in the paint more, which leaves Horford on the perimeter playing D (which is bad).  Starting Jerebko (or maybe even Kelly) would help solve that

That pretty much sums it up. Certainly AB and Crowder have upped their defensive energy in the last several weeks, too, along with Amir getting a bit more active, but the rebounding issues and playing Horford out of position due to Amir's decline in mobility are the real issues with our defense this year.

[tarheelsxxiii]

I'm not sure this type of analysis holds up.

For instance, if you look at the 3-man lineup of Horford, Crowder and Amir, the defense gets better if you add IT as the 4th guy as opposed to Bradley.  Does that mean IT is a better defender than Bradley?

Just because somebody uses advanced stats doesn't mean they're using them correctly.  Plus, DRtg is a flawed statistic to begin with. For instance, it tells us that Marcus Smart is a worse defender than Tyler Zeller.

Exactly.  And we continue to win by outscoring opponents lead by Thomas' wizardry. So is this really an issue to be concerned about?

[jpotter33]

I'm not sure this type of analysis holds up.

For instance, if you look at the 3-man lineup of Horford, Crowder and Amir, the defense gets better if you add IT as the 4th guy as opposed to Bradley.  Does that mean IT is a better defender than Bradley?

Just because somebody uses advanced stats doesn't mean they're using them correctly.  Plus, DRtg is a flawed statistic to begin with. For instance, it tells us that Marcus Smart is a worse defender than Tyler Zeller.

Exactly.  And we continue to win by outscoring opponents lead by Thomas' wizardry. So is this really an issue to be concerned about?

Yes, because the game slows down and switches entirely in the playoffs. Boston trying to simply outscore opponents won't work then, especially when the opposing defenses start clamping down.

[hpantazo]

I'm not sure this type of analysis holds up.

For instance, if you look at the 3-man lineup of Horford, Crowder and Amir, the defense gets better if you add IT as the 4th guy as opposed to Bradley.  Does that mean IT is a better defender than Bradley?

Just because somebody uses advanced stats doesn't mean they're using them correctly.  Plus, DRtg is a flawed statistic to begin with. For instance, it tells us that Marcus Smart is a worse defender than Tyler Zeller.

Exactly.  And we continue to win by outscoring opponents lead by Thomas' wizardry. So is this really an issue to be concerned about?

I don't think Thomas is the problem, but giving up 60 points in a half to virtually every team in the league is certainly a major problem we have to deal with if we hope to go anywhere in the playoffs.

[hpantazo]

If Amir's decline in lateral quickness is the major problem, which I believe, then we need to get a big man with adequate lateral speed on defense to anchor our team D.

Who can we get to fill that need? Guys like Bogut or Nurkic wouldn't do it.

[Roy H.]

The Celtics rank 12th in Opp FG% and 4th in Opp 3PT%, and are 11th at forcing turnovers. I think the biggest issue, as mentioned, is our lack of defensive rebounding (2nd worst), along with a tendency to foul too much.

[hpantazo]

The Celtics rank 12th in Opp FG% and 4th in Opp 3PT%, and are 11th at forcing turnovers. I think the biggest issue, as mentioned, is our lack of defensive rebounding (2nd worst), along with a tendency to foul too much. too many bad calls against us.

[notbillsimmons]

Why don't you post the actual link.
Coach Nick says our defense get better when Kelly Olynyk is on the floor with Al Horford.

That was the whole point of the video. He only touched on Isaiah and his good effort on defense for 1 minute.

https://www.youtube.com/watch?v=aJdtTfbtzLI

[hpantazo]

Why don't you post the actual link.
Coach Nick says our defense get better when Kelly Olynyk is on the floor with Al Horford.

That was the whole point of the video. He only touched on Isaiah and his good effort on defense for 1 minute.

https://www.youtube.com/watch?v=aJdtTfbtzLI

Well that makes a lot more sense, especially related to Amir's lack of lateral quickness.

[PhoSita]

The Celts' most used lineup last year was Thomas - Bradley - Crowder - Johnson - Sullinger.

That lineup had a 109 Offensive Rating and a 107 Defensive Rating, and had a +/- of +21 in 722 minutes for the season.

This year, the Celts' most used lineup is that same one only with Horford in place of Sullinger.

That lineup has a 117 Offensive Rating and a 111 Defensive rating, and is +29 in 227.5 minutes this season.


I have a hard time believing that lineup can't perform at least as well defensively with Al Horford as they did with Jared Sullinger, though defensive rebounding is likely the factor to consider there.  Either way, it doesn't seem like Isaiah is tanking the defense to the point that the team isn't good.

Of course, the common trend is that lineups with Isaiah instead of Marcus Smart are considerably worse defensively.  That's not a shocker since Smart is a very good defender and Isaiah is tiny.



Now, the lineup Coach Nick is referring to, I think, is the one with Thomas, Horford, and the defensive threesome of Bradley, Smart, and Crowder.

Is it shocking to see that lineup with a 130 defensive rating?  Kind of yes.  But on the other hand, you've got a tiny point guard and an undersized center who is a below average rebounder for his position.  Then you flank them with three guys who are 6'2'', 6'3'', and -- being generous -- 6'6''.  There's simply not enough size in that lineup to get by except against the smallest opponents.


The Celts have a quality top lineup with Amir and Horford in the frontcourt.  That lineup is not amazing defensively if Isaiah is on the floor, but it becomes pretty great with Smart in there.  With Isaiah, it scores a crap-ton of points, and is generally a very effective lineup.

[greece66]

@Pho

You are right that the line up with Smart instead of Amir has a DefRtg of 129.6

but my understanding is that 'coach Nick' is talking about the IT, AB, Jae, Amir, Al lineup which has a DefRtg of 107.1

Here is a link of the vid at the moment where he shows the ratings

https://www.youtube.com/watch?v=aJdtTfbtzLI#t=1m4s