Worse defense since the 2006-2007 season?

[PhoSita]

More meaningful number when it comes to opponent three-point field goals is the number of attempts since there's very little a team can do to affect a three-point shot once it's actually launched.

In the era of Thibodeau defenses, the best measure of defensive effectiveness might be the average degree of difficulty and / or overall efficiency of the shots that opponents take against a team.

[Alleyoopster]

I don't think the Celts have the size or length on the wing, or the athleticism, strength, and quickness in the interior, to really be a great defensive team.

Stevens will cobble this unit into an above average defense again, though, I have no doubt.

The offense will be the bigger issue.

Still, I think we can expect to see a number of games where the Celts get pounded inside.

The nice thing about the modern NBA, and probably part of the reason why we haven't emphasized getting a rim protector, is that there's only a handful of teams that can consistently pound the ball inside.  Defending the perimeter, especially the 3, seems more useful across the board these days.  I think we were top 5 in opponent 3 pt% last season (can't look it up), so hopefully we can keep it up.

Well, I don't know, I think "pound inside" has just changed in how it looks.  Once upon a time, defending the paint meant having big post defenders who could give guys like Dwight and Bynum trouble (e.g. our friend Perk).

Now, pounding inside is all about attacking the rim out of the pick and roll and on backdoor cuts off perimeter ball movement.

I think the Celts lack the length on the perimeter to make it really hard for opponents to get passes inside, and they lack big men with the lateral quickness, explosiveness, and length to swallow pick and rolls and discourage shots at the rim.

So I don't think the Celts will be bad defensively, like I said, but I expect them to get exposed inside fairly often, while making the most of the talent they have, especially defending the perimeter.

TP - Excellent observation and analysis.  I want you in the front office advising Danny on any future trades.

Pick and rolls rule
The days of the great individual defender may have been diminished with the incessant use of pick and roll ball movement. Having length, lateral quickness and explosiveness would be great contributors to better defense.  Strength and intelligence wouldn't hurt either. 

I wonder if more emphasis is now placed on anticipating picks than has been done in the past?   

[Celtics4ever]

The days of the great individual defender may have been diminished with the incessant use of pick and roll ball movement. Having length, lateral quickness and explosiveness would be great contributors to better defense.  Strength and intelligence wouldn't hurt either

I don't think this is the case.    Good defenders seem to always stick on, even as specialists if they are truly good at it.   If two players are close, you take the better defender most of the time, too.  Length, quickness and explosiveness helps on drives too.

[Csfan1984]

I was just about to post about the D in preseason. The D has looked bad and it's teams running the same plays against them that is even more annoying. I said this last year, the C's need to diversify their defensive schemes more. If they don't we will see a team in the 20s in defensive ranking.

[Rondo9]

I don't think the Celts have the size or length on the wing, or the athleticism, strength, and quickness in the interior, to really be a great defensive team.

Stevens will cobble this unit into an above average defense again, though, I have no doubt.

The offense will be the bigger issue.

Still, I think we can expect to see a number of games where the Celts get pounded inside.

I think they have a very good perimeter defense but they are bit soft on the interior though.

[incoherent]

The D won't be bad. It was decent last year and we got better interior D in our starting lineup.

We have the 3rd best steal % and 12th best block % in preseason so far, which is better then nothing I guess.

But our defense rebounding has been pretty bad.

It's only preseason hard to say. The stats don't mean anything with so many rookies playing for all teams.

[Celtics18]

I expect us to finish in the top ten in Defensive Rating for the season.  We were twelfth last season, and we should clearly be improved on that end this season.

The addition of Amir will help a lot, as will the added time together for the core of the team.

[trickybilly]

Some of the Nets easier scoring opportunities were not from defensive lapses rather they came off Celtic turnovers, e.g., poor passing or players losing the ball trying to dribble between players.
As for double teaming/trapping that backfires too.  Zeller tried that once near the top of the key and it lead to an easy score.  Also, RJ looked to help out teammates who were guarding players near the top of the key and left his man or someone else's man open in the corner.  This happened with a couple players.  I believe Turner was a victim of this as well at the beginning of the game. 

My one concern was that there seemed to be a lack of communication between switching assignments.  One time Marcus had to come from the middle of the key to the corner to try to block a shot as someone was wide open.  Why that happened I'm not sure.  Maybe it was a combination of missed assignments?

Not sure what advanced stats say on traps generally, but I don't like em. If the guard notices the trap early enough he can dribble/pass out of it and then your  defensive structure is broken and two or three decent passes while the D scrambles, leads to a wide open look or a dunk.