The evolution of college basketball offense
Offensive philosophies have changed over the past decade, and Kentucky has been slow to keep up.
In the novel “Alice in Wonderland”, Alice meets the Red Queen. While talking, the Red Queen implores Alice to run; Alice runs faster and faster, but notices she is staying in the same place and finds this very strange. The Red Queen tells Alice “It takes all the running you can do, to keep in the same place.”
This idea has been adopted by biology to explain evolution and the idea that organisms must keep evolving specifically because their competition in nature is also evolving, so they must keep pace. The same idea can be applied to college basketball.
Over the past decade, college basketball offenses have changed their strategies to improve their effectiveness. The fiercely competitive nature of college basketball mirrors that of the natural world, or of the Red Queen’s bizarre domain, and college basketball coaches need to keep improving their own approaches or risk falling behind slowly but surely. This season has shown this to be true for Kentucky as the Wildcats’ approach on offense has not kept pace with their competition, and Kentucky now struggles to put together a competent offense despite recruiting only the best prep players.
In this edition of Hoops Insight, I will explain how college basketball offenses have evolved, how Kentucky has generally maintained a strong offense despite a lack of evolution, and how this season has betrayed the Cats’ usual approach.
Better and better shooting
From 2012 through 2019, team effective FG% in halfcourt offense improved substantially. There was a dip in 2020 when the NCAA moved the three point line back, but 2021 has restarted the upward trend. I charted the eFG% each year that marked the 75th percentile (top 25%), average, and 25% percentile (bottom 25%), and the trend has been visible across the spectrum.
A team that had an effective FG% of 51% in 2012 would ranked about 85th in the country, but by 2019 that same 51% would rank just about 162nd. To maintain an 85th place ranking, a team would have to improve from 51% in 2012 to about 52.8%. You have to keep running as fast as you can just to stay in the same place!
The rule change in 2020 helped blunt this a bit, but the effect is still there. To rank 85th in 2021, a team would need an eFG% of 52%.
Not driven by more skill
What has caused this improvement in effective field goal percentage? One idea would be that college basketball players are more skilled and shoot better from various areas of the floor. However, the data doesn’t support that. For example, three point shooting has not significantly increased over 2012 to 2021.
There was a dip in 2020 with the line moving back, but overall the trend was flat from 2012-2019. A team in the 75th percentile in 2012 hit 36.3% of their threes, and a team in the 75th percentile in 2019 hit 36.2%. This season, a team in the 75th percentile hits 36.1%. You don’t need to improve your 3 point shooting to maintain your position among your competition.
The same is true with shooting at the rim.
The best teams, average teams, and worst teams have shot about the same percentage at the rim over the past decade.
Midrange shooting has seen some small improvement, but not a lot.
A team in the 75th percentile of midrange shooting would need to hit 38% in 2012, but 40% now. The 50th and 25th percentile have seen smaller but similar improvements.
So, if teams shoot better overall but not from distinct areas of the court, what’s happening? The answer is that teams have improved their strategic approach to take more shots from areas that yield more points per shot.
More detailed analysis has been done at the NBA level than at college regarding shooting and points per shot at specific distances, due to the greater availability of specific location data. This analysis shows two key things. First, field goal percentage does not significantly increase between 6 feet and 25 feet away from the basket:
Image from Kirk Goldsberry’s book, Sprawlball
NBA players hit roughly 35-40% of their shots from 6 feet away from the basket, and roughly 35-40% of their shots from 25 feet away. Meanwhile, the shots from 25 feet are worth 3 points compared to 2 points from 6 feet. When you look at this data in terms of points per shot, you see where the most productive areas on the court are.
If you want to generate 1 point per shot, you need to hit 33% of your threes or 50% of your twos. The only areas where NBA players do that are 1) at the rim, or 2) beyond the three point line.
College basketball might be different, but that difference is likely to be miniscule. You can see in the charts above how teams have shot between the rim and three point line; they struggle to hit 40% from there. That’s worth 0.8 points per shot…well below what shots around the rim or from the three point line are worth.
Offensive strategies have adapted
College basketball coaches have adapted their offensive strategies somewhat over the past decade to respond to this opportunity. As the charts below show, teams have increased the percentage of shots they take at the rim and from three, and decreased their shots taken from the midrange.
The shift has been most dramatic in the rise of threes and reduction of midrange shots. In 2012 32 teams took at least 45% of their shots in the midrange; this season, 3 do. In 2012 30 teams took at least 40% of their shots from three; this season, 89 do.
The very best teams on offense tend to favor shots at the or threes and not the midrange. From 2012 through 2021, no team ranked in the top 20 of effective FG% who was also in the top 20 in % of shots taken from midrange. During that same time, 22 teams were in the top 20 in effective FG% who were also in the top 20 in percentage of shots at the rim, and 36 who were in the top 20 in percentage of shots from three.
Kentucky has largely failed to adapt
The Wildcats under John Calipari have not kept pace with this evolution. Just take a look at how their shot distribution has stayed consistent:
In 2012, UK took 31.0% of their shots at the rim, 42.6% from midrange, and 26.5% from three; they took the 180th most shots at the rim, 59th most midrange shots and 303rd most threes
In 2021, UK is taking 30.1% of their shots at the rim, 40.8% from midrange, and 29.1% from three; they take the 278th most shots at the rim, 10th most 2 point jumpers, and 325th most threes
In a world where you have to keep running as fast as you can just to stay in the same place, Kentucky has jogged and fallen further behind.
Despite this lack of evolution, Kentucky has had good offenses under John Calipari. Before this season they had never been worse than 38th in KenPom’s offensive efficiency rankings, and only worse than 24th in the 2012-13 season. So, how was Kentucky able to keep their offense elite despite disadvantages in shot selection?
The anwer lies in the other key areas of offense and their relationship to shot selection; specifically free throws and offensive rebounding. UK’s effective FG% has ranked in the top 60 only once since 2014, and has been outside the top 120 4 times in that span. But in that same time, Kentucky has ranked in the top 20 in offensive rebounding 5 times and free throw rate 4 times. UK has only ranked outside the top 50 in offensive rebounding once; last year they were 81st. The Cats have only been worse than 31st in free throw rate twice; 142nd in 2016 and 122nd this season. At the same time, most of college basketball has gotten worse at offensive rebounding and drawing free throws:
With the rise of 3 point attempts, offensive players are farther from the basket and are in poorer position for offensive rebounds. Similarly, players shooting threes are less likely to draw free throws. So as Kentucky has fallen behind in shot selection, they have bolstered their advantage in offensive rebounding and drawing free throws. But what happens when that goes away?
This season has been the worst of everything
This season Kentucky is not able to mitigate their shot selection weaknesses in other areas. UK is 35th in offensive rebounding. That is actually a relative strength this season, but that’s the 3rd worst ranking for a UK teams since 2014. Meanwhile, UK cannot get to the free throw line at all. The Cats are 122nd in free throw rate, the 3rd worst rate under Calipari behind only 2016 and 2011. In those seasons, however, Kentucky was elite in other areas. In 2011, UK had the 10th lowest turnover rate in the NCAA and the 9th best 3 point FG%. In 2016, UK had the 12th best offensive rebounding rate and 30th best 2 point FG%.
This season Kentucky has struggled in the skill areas of offense, and has compouned this with a poor strategy. UK is decent in FG% at the rim at 79th in the NCAA but 278th in taking shots there. Meanwhile UK takes the 10th most 2 point jumpers, but is 283rd in FG% on these shots. This is a disaster, point blank.
Some reasons for optimism
Kentucky has started to improve their shot selection, even as their midrange shooting languishes. Their last 3 games have seen Kentucky take 46% of their shots in halfcourt offense from three, compared to just 23% from midrange and 30% in the paint. This has also been the first stretch where Kentucky had an effective FG% above 48% for 3 games in a row. Kentucky has been hot from three, hitting 49% of their halfcourt looks, but they’ve hit well from three before and shot poorly overall. On Jan 26th vs Alabama, UK hit 44% of their halfcourt threes but posted an effective FG% of just 45% because over half their shots in halfcourt came from midrange, and the Cats hit 18% of them. Against Mississippi State, UK hit 53% of their threes and 100% of their shots in the paint in halfcourt offense, but took 30 of 49 shots from midrange and hit just 5 of those.
The last 3 games have seen Kentucky’s best offense of the season, and it’s coincided with better shot selection. The team isn’t shooting well from anywhere but three:
8-43 from midrange (19%)
36-66 in the paint (55%)
33-76 from three (43%)
But UK is overcoming the poor shooting inside the arc by taking more threes. It’s been difficult for UK to draw free throws or control turnovers this season, but changing their shot selection is something they absolutely can do and have done at times. The Wildcats need every bit of marginal advantage to get any kind of winning momentum, and the biggest thing they can do is to admit their offensive strategy of the past decade isn’t working this season and take a better approach.
Great work here