2018-19 Duke: The Zion Show
Duke had a generational talent in Zion Williamson, but fell short of their goals.
This is the first in a 4 part series about the 2018-19 Duke Blue Devils. Part 2 will come out on Thurs, Nov 19.
Duke’s basketball recruiting for the Class of 2018 really couldn’t have gone much better. The Blue Devils were bringing in the latest “best freshman class ever”, with the #1, #2, #4, #13, and #37 recruits according the the Recruiting Services Composite Index (RSCI). They were going to be counted on heavily, as Duke was returning only a handful of bench players from the previous year’s team…and only 1 (Javin DeLaurier) had even averaged 10 minutes per game. The headliner was Canadian wing RJ Barrett, who was ranked #1 in the class and was named preseason All-ACC First Team. Cam Reddish (#2 in the class) and Zion Williamson (#4) were tabbed for preseason 2nd team All-ACC as well.
If you’re reading this you probably know how it went. Zion was a force of nature, earning one-name status like so many legends do at a precocious age. The Blue Devils ended up going 32-6 on the year, winning the ACC Tournament, and earning a #1 seed in the NCAA Tournament. The season ended on a down note however, as Duke narrowly avoided 2nd and 3rd round upsets in the NCAA Tournament to UCF and Virginia Tech but succumbed to Michigan State by a single point in the Elite Eight. It felt a bit like potential unfulfilled.
Is that the right narrative? Do the numbers tell a different story? If not, why did things come up shorter than expected? Over the next few editions of Hoops Hindsight, I’ll tell the story of the 2018-19 Duke Blue Devils.
Athleticism channeled on offense and defense
At times the 2018-19 Blue Devils seemed like a force of nature. They opened the season with a 34 point evisceration of a Kentucky team that would make the Elite Eight. They only lost 3 games, by a combined 7 points, in games where Zion played more than 1 minute.
Zion was nearly unstoppable at the rim. Per hoop-math.com, he was 2nd nationally in effective FG% at 70.8%, with almost 80% of his shots coming at the rim. In fact, Zion made 248 baskets at the rim that season, 40 more than any other player.
This sheer talent advantage helped Duke stand out in a number of key stat categories. Per kenpom.com, they were:
7th nationally in offensive efficiency and 6th in defensive efficiency
4th in 2-point field goal percentage
14th in offensive rebound rate
15th in 3-point FG% allowed and 18th in 2-point FG% allowed
3rd in block rate and 5th in steal rate
8th in free throw rate allowed
Those last 2 stats are a very unusual combination, to have a team that is ball-hawking but avoids fouling. Washington and Auburn were both also in the top 10 for steal rate and block rate, but Washington was 214th in free throw rate allowed and Auburn was 264th. The Synergy rankings for Duke on defense concur that they were a very effective group, with all of their top 6 players rating Good, Very Good, or Excellent, and the team rating as Excellent in defending each of the 4 most common play types they faced (Spot Up, Transition, P&R Ball Handler, and Isolation). Another interesting nugget in the Synergy data caught my eye as well: on all of the 5 most common play types they faced (the above plus Cuts), Duke forced turnovers more frequently than they committed shooting fouls. In fact, they are the only team I can remember who accomplished this on plays Synergy labelled as Cuts. For comparison’s sake, the 2018-19 Texas Tech Red Raiders were ranked #1 in defensive efficiency, and they fouled more than twice as often on cuts as they forced turnovers. It takes overwhelming athleticism to recover against a cut, challenge the ballhandler, and avoid fouling, but Duke was as good at it as anyone.
Usually doomed by shooting struggles
Duke wasn’t perfect by any means, however. They were a poor outside shooting team, ranking 327th nationally in three point percentage. They also struggled at the foul line, ranking 252nd from there. Duke’s propensity for challenging shots also allowed opponents to collect 30% of their offensive rebounds, 238th worst in the nation.
Duke’s 6 losses all came to opponents ranked in the top 40 by KenPom, so they didn’t have any real stinkers. Most of Duke’s stats were worse in these games, but that’s to be expected when you play against stronger teams. What is surprising, however, is that Duke’s effective FG% in those games was actually about 1.5% worse than those teams usually allowed, despite Duke being one of the top offensive teams in the country.
In their 6 losses, Duke hit 51% of their twos and 26% of their threes; that’s down from 59% and 31% for the season (excluding garbage time). Most of their other offense stats did not drop off as much in their losses, however. Duke’s turnover rate was 18% in losses and for the season, their offensive rebounding rate was 33% in losses and 35% for the season, and they shot free throws just about as often when they lost (a hard thing to do, since you get more when opponents foul to catch up). The shooting was what fell off a cliff. In a later article I’ll dive into Duke’s shooting and what drove good and bad trends.
A major dropoff without Zion
You might remember the incident with Zion’s shoe in the February 20th game against North Carolina. He played only 1 minute that game, then missed the next 5 with knee trouble. As you’d expect, Duke suffered quite a bit from the absence of their star player.
For the season, Duke had an adjusted scoring margin of +35 pts/100 possessions (excluding garbage time). In the games Zion missed, that dropped to +20. That’s the difference between one of the top 2-3 teams in the country and maybe the 20th best team. 20th best is still very good, but it’s not prime title contention.
Without Zion, Duke’s offense focused more on three pointers. Threes made up 37% of their shots for the season, but nearly 44% when Zion was injured. As I mentioned before, outside shooting wasn’t a strength for Duke, and then only hit 27% of their threes during Zion’s absence.
Another major area they missed Zion was forcing turnovers. Zion himself ranked 32nd nationally in steal rate, leading the team. For the season Duke forced turnovers on 20% of opponent possessions, but they only did so on 15% of possessions while Zion recuperated. In a later article I’ll dig more into Zion’s absence and how it affected Duke.
Outstanding in the clutch
It was difficult for anyone in the country to match up with the talent and explosiveness of Duke’s top players. Nowhere did this play out truer to form than in the last 5 minutes and overtime of games, when Duke was very difficult to subdue. Excluding garbage time, Duke played 202 possessions over the season during the last 5 minutes and overtime. They were +54 in those possessions, good for a sparkling adjusted margin of +47 per 100 possessions. Out of 24 games where the last 5 minutes saw the outcome still in doubt, Duke was outscored by their opponents in only 4 of them:
By 4 points against Auburn (won 78-72)
By 5 points against Syracuse (lost 95-91 in OT)
By 1 point against North Carolina on March 15th (won 74-73)
By 1 point against Michigan State in the Elite Eight (lost 68-67)
The Syracuse loss was notable for the absence of Cam Reddish, one of Duke’s talented freshmen. In the final 5 minutes + OT when Duke had all 4 of their freshmen, they were a simply ridiculous +36 in 87 possessions, good for a stunning adjusted margin of +67 per 100 possessions. They put up an effective FG% of 64% in these situations and forced turnovers on 21% of opponent possessions.
In an upcoming article, I’ll look at Duke’s performance in late game situations and what set them apart.
I hope you are as interested as I am to dive into the story of the 2018-19 Duke Blue Devils. Zion was truly a rare breed of college athlete who left a lasting mark on the game. Over the next 3 articles I hope we can all learn a little bit more about a fascinating team, what made them special, and why things came up just a bit short.