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UNC Basketball: Despite a rough night against Syracuse, UNC’s defense is playing at elite levels

The Tar Heels are on pace to be one of Roy Williams’ best defensive teams since he’s been back in Chapel Hill.

NCAA Basketball: Syracuse at North Carolina Bob Donnan-USA TODAY Sports

After Tuesday night’s win against Syracuse, North Carolina holds a 23-5 record and remains atop the ACC standings at 13-2. As with most seasons, we’ve seen potential narratives from every direction trying to explain how UNC has once again positioned itself among the nation’s top teams. This team has been dissected on a daily basis since the season started. That is not unique to this just this season, but the amount of topics that have left fans concerned or excited has been... extreme.

In no certain order, they include:

  • Coby White’s growth and development
  • Coby White’s struggles
  • Nassir Little’s usage
  • Nassir Little’s lack of usage
  • A lack of an “elite” big man
  • Luke Maye’s struggles
  • Luke Maye’s dominance
  • Injuries and a depleted bench
  • Key production from the bench
  • Seventh Woods’ resurgence
  • Seventh Woods’ regression
  • Seventh Woods’ re-emergence
  • UNC can only win if they can make three-pointers
  • UNC can win without making three-pointers
  • *INSERT ANY TOPIC*

Seriously folks. It’s exhausting and none of that covers the most recent topic du jour.

Elite defense.

I get it. After Tuesday night’s barrage, how can one reasonably make the argument that UNC’s defense is really that good? Stick with me. It’s not that hard.

After the Heels exacted revenge on the Louisville Cardinals, I made a case that UNC’s defense was more effective than people realized. A week later, our own Joe Carpenter expressed specific concerns in his weekly Tar Heel Hangover, falling on the opposite end of the spectrum. With three games remaining in the ACC regular season, there may not be a clear cut answer, but there are some encouraging trends. Let’s take a look. (Sorry, Joe!)

Points Per Possession

If you’re not familiar with points per possession, or PPP, the idea is simple. Score more points per possession than your opponent. That seems obvious, but turnovers, offensive rebounds, and free throw attempts, mean not all possessions are equal. Different programs have different philosophies on what is “good” or even how to define a possession. North Carolina’s equation (below), for example, does not match the “industry standard”.

Styles of play within programs today and in previous eras have led to differing opinions when using advanced stats. When Dean Smith effectively invented this metric in the 1950’s as an assistant at Air Force, he set the desired goals at .85 PPP on offense and .75 PPP on defense. Times change. To keep it simple, a very basic working model for fans of today’s game is you want your team to score more than 1.0 PPP and hold opponents to less than 1.0 PPP.

With that in mind, the Heels have held an ACC opponent below 1.0 PPP in the regular season eight times. Their record in those game? 8-0. That includes three consecutive games prior to Syracuse’s out of body experience behind the arc. (Shoutout to DadgumBoxScores.com)

The ACC expanded the regular season to 18 games in 2013. In the six years since, UNC’s final totals of such games are as follows; 10, 11, 7, 6, 6, 3. With three games remaining, this year’s total could also reach 11.

On the surface, it appears that accomplishing this feat eight times in 15 games is impressive. What about 2013 (10 games) and 2014 (11 games), though? Neither was a particularly great year for UNC by our fanbase’s (rightfully) lofty standards. There is an easy explanation.

Defensive Efficiency

Another useful tool is Defensive Efficiency, which is essentially PPP * 100. Whereas PPP measures points a team has given up per each individual possession, Defensive Efficiency measures the total points a team would allow over 100 possessions. Going with that theme, Ken Pomeroy has chosen DE rather than PPP to create a metric called Adjusted Defensive Efficiency (AdjD) which factors in the strength of a team’s opponents. It’s one of the closest approximations we have to an “even playing field” when comparing teams.

This year’s team currently is 14th in the nation with an AdjD of 91.5.

Is that good, you may ask? Yes. Yes it is.

Here’s the complete list of seasons where UNC has had a better AdjD.

2005 - 89.7, 5th nationally
2007 - 89.6, 4th nationally
2011 - 89.6, 5th nationally
2012- 90.7, 11th nationally

That’s it. That’s the list. A title and three Elite Eights*. For what it’s worth, before Tuesday, the AdjD was 90.4, so this is clearly a fluid situation. Those 2013 and 2014 squads that held 21 total regular season ACC opponents to less than 1.0 PPP? They had an AdjD of 95.1 and 94.2. If this season ended today, the 2013 and 2014 squads would be the 14th and 12th best in Roy’s 16 seasons.

*God, I hate Creighton.

Strength of Opponents

So, why did the 2013 and 2014 teams do so well with PPP, but flounder in defensive efficiency? According to KenPom, they played relatively weak competition. In 2013 the overall SOS was 19th toughest in the nation. 2014 was worse, slotting in at 23rd overall.

The strength of schedule for 2015-2019 was much stronger. From 2015-18, the Heels’ SOS finished 2nd, 8th, 6th, and 1st. This year’s team currently sits at 12th. With the regular season, ACC Tournament, and NCAA Tournament remaining, the schedule can still gain strength.

In ‘13 and ‘14, UNC held more opponents to fewer PPP because those opponents weren’t good and masked other deficiencies that became noticeable against top competition. In 2013, North Carolina was 0-7 against team in the KenPom top-30. This season, they are 6-5. In one of those losses, they even held their opponent to 0.96 PPP (Kentucky).

Admittedly, those tougher schedules are buoyed by stronger non-conference schedules in each of those seasons. The counterpoint is the ACC has also been stronger from 2015-2019. There isn’t one “right” answer, but no matter how you slice it, UNC’s defense has been on par with the best of the Roy Williams era.

(Want another reason for optimism? KenPom ranks the overall offensive efficiency of UNC’s opponents as the third highest in the country. Whatever metric you choose, the conclusion is the same. The Heels are playing stout defense against some of the best teams and offenses in the country).

What does it mean?

At this point, not much. On paper, North Carolina is primed for a deep run. Early April is within the realm of possibility. Set your expectations accordingly.

Games, however, aren’t played on paper, and there are valid concerns with this team. Until recently, the soft spot of North Carolina was in the middle. In all five of its losses, UNC has either been tied or outscored in the paint by their opponents. Four of those teams scored 30 or more points near the basket. Sometimes the game is just that simple.

Fears about “needing” an “elite” big man have been slightly eased over the past few weeks. As long as Garrison Brooks continues his development, despite often being underappreciated, North Carolina can maintain their momentum. The same can be said for Nassir Little and his ever-expanding role as he starts to show signs of a deeper understanding of the game.

It must be said that with three games remaining in the regular season, including the rematch against Duke, it’s possible for these numbers to regress. A pessimist would say that regression began last night. (Though, that seems unfair to Syracuse, who hit some really tough shots.)

Of course, that also means there’s plenty of time for UNC to continue to be one of Roy Williams’ most dominant defensive squads he’s ever had in Chapel Hill. If that happens, the Heels could dance all the way to the Final Four.

Again.