A few years ago, the NBA had an analytics movement. Similar to the one that occurred in baseball years prior, some of the long-held strategies were challenged. Teams began to prioritize efficiency over counting stats. This resulted in personnel changes; front offices began to favor stretch players and smaller lineups. Coaching staffs made strategic adjustments to improve ball movement, spacing, and pace at the expense of hero-ball.
Front offices tracked everything – shots, touches, lineups, player’s on/off court impact, expected shot value, etc. One of the earliest findings was that the corner 3 has the highest expected shot value.
Data from the 2016-17 NBA season shows that corner 3s had a 3P% of 39.4%, while center and wing 3s were shot at 34.4% and 34.9% clips, respectively. Expected shot value is calculated using the location’s shooting % and point value. Therefore, the expected point value of a corner 3 in the NBA is 1.182 (.394 x 3).
This marginal lift on corner 3s became a competitive advantage for the teams that studied the play types that generate these shots, why there was a lift, and how they could shoot more of them.
So now everyone’s wondering: Does the lift on corner 3s exist in college basketball?
Yes. An analysis of 2016-17 NCAA D1 data shows that there is a 2.5% increase in 3P% between corner 3s and non-corner 3s, or above the break 3s.
Some have argued that the corner 3’s value was due to the shorter distance to the rim as the NBA 3-point line is 22’ feet in the corner and extends up to 23’9”. However, the college 3-point line is equal at all spots along the line at 20’9” and there is still a substantial lift on corner 3s.
Furthermore, using NBA data, a comparison can be made between corner 3s taken from 22’ and 2-point shots also taken from 22’. The 22’ corner 3s are made at a 39.4% clip compared to a 37.7% clip on 22’ shots from inside the arc. It’s not distance.
So, then, what is the cause of the lift on corner 3s?
An analysis of shot quality, using data from NBAsavant.com, provides the best explanation. The graphic below shows average dribbles, average touch time, and average defender distance for corner 3s and above the break 3s.
The corner 3 is less contested, on average, and a higher percentage of these shots are catch and shoot, which are made at higher rates than shots off the dribble. The database doesn’t provide true catch and shoot data, but 91% of the corner 3s were shot without a dribble compared to 72% for above the break 3s.
This suggests it’s all about what happens before the shot – the corner 3 is the byproduct of the possession.
The teams that take the most corner 3s get the defense to collapse and lose their assignments. The best ways to get a corner look is to penetrate the defense or getting a touch in the paint. Defenses that decide to double team players in the post risk getting beat on a pass to the corner.
Is it possible to identify the teams with the highest lift on corner 3s through a specific stat?
There isn’t a metric in college basketball that measures these types of possessions. However, the teams with the highest lifts on corner 3s had a player in common – a 6’8”+ big man who shot at least 60% on 2s, an assist rate above 8%, and a usage rate above 20%.
These are taller big men who dominate in the paint and frequently draw double teams or extra attention. Once the double comes, they are adequate passers to find the open man in the corner.
Teams with these players shot 5.1% better on corner 3s than above the break 3s - 2.6% better than the D1 average lift.
Which teams had the highest lift last season?
Creighton – 51% on Corner 3s (14.5% lift Corner 3 vs Above the Break)
Middle Tennessee – 44.1% on Corner 3s (9.4% lift)
Texas A&M – 40% on Corner 3s (9.1% lift)
Shooting at a high percentage from the corner is only part of the equation. Teams need to try to create as many opportunities for corner 3s as possible.
The NBA has used the data to their advantage – the NBA average for percentage of 3s that are corner 3s continues to increase. The chart below shows the percentage of 3s from the center, wing, and corner for the NBA and NCAA.
NBA teams take 7% more 3s from the corner than D1 teams – they studied this shot and know how to take more of them. Corner 3s remain an untapped goldmine in NCAA basketball right now. It’s time college coaches study and follow their NBA counterparts.
Some have already caught on. In a press conference last year, Marshall Head Coach Dan D’Antoni, brother of 3-point revolutionist Mike D’Antoni, said, “The best shot in basketball is that corner three.” Who listened?
“We don't measure our performance on if shots go in. We measure it on -- I don't mean to be too analytical -- expected shot value.” – Brad Stevens, Boston Celtics Head Coach