Shabazz Napier has been awful in the summer league.
This is disconcerting because no small part of his putative appeal is his polish: He’s 23 and appeared to be ready to step into the NBA, contributing more or less immediately. If the Miami Heat aren’t at least a little worried by the results of his first foray into professional basketball, they should be.
In fairness, “awful” might not be the best word to describe the rookie’s play. He’s been worse than that.
Over the course of five games in Orlando, Napier averaged 9.2 points on 27.3 percent shooting to go along with 3.0 rebounds and 4.6 assists.
Then, after regrouping, collecting himself and heading back to the old drawing board...he averaged 10.3 points on 27.7 percent shooting in Vegas, chipping in 1.3 rebounds and 2.8 dimes for good (bad? putrid?) measure.
What jumps off the page here, though, isn’t just his aggregate inefficacy; its his clockwork consistency. In nine summer league games, he’s only shot better than 50 percent from the floor once—when he went 4-of-5 in a July 12 92-81 victory over a group of young men wearing Houston Rockets uniforms.
Nor has he shown any discernible improvement along the way. In the final four games of the schedule, he shot 9-of-42, 21.4 percent.
Napier, in a conversation with ESPN.com’s Michael Wallace after his lackluster debut, conceded that the pro game wasn’t coming to him as easily as success did at the college level he dominated for three seasons, culminating in a national title last spring.
It’s a big adjustment. I’m unable to do a lot of things I was on the college level. I’ve got to find the adjustments on how to do those things. I’ve still got the college game coming in. We’re learning on the fly, and we’re going to make big mistakes. This is a different game.
It certainly looks like he’s playing a different game.
So Napier’s been tremendously ineffective for Miami. And while the instinct is to dismiss summer league as simply small sample-size theater—and theater that often resembles NBA basketball in the way a high school musical resembles Broadway—this is a misleading impulse.
The summer league matters. Particularly for rookies.
Take it from ESPN Insider Kevin Pelton. According to Pelton (subscription required), there’s a fairly weak correlation between summer league play and regular-season performance—it comes out to just .288, for folks who are interested in particulars—but that doesn’t tell the whole story.
When Pelton investigated the meaning of the Orlando and Vegas tournaments last summer, he found something interesting. The league has very little predictive validity for veterans, but for rookies, it can tell us a great deal. According to the stat maven:
Veteran players who were in the league the previous season have an even smaller correlation of .101 between 2012 summer performance (as measured by my per-minute win percentage rating) and 2012-13. Once we account for how well these players were projected to play in 2012-13, their summer-league stats have zero predictive value.
By contrast, the correlation of .463 for rookies is far higher.
This is much higher. Pelton wrote that rookie summer league performance is nearly as predictive of regular-season success as college statistics are (.468).
None of this is a death knell for Napier's NBA hopes, of course. In the course of the same study, the author discovered that certain statistics are more meaningful than others vis-a-vis extrapolating regular-season performance from the summer league. Shot blocking and defensive rebounding are particularly predictive of what’s going to happen in the games that count. And what isn’t? Field-goal percentage. According to Pelton:
Conversely, shooting during the summer tends to be much less predictive than randomness alone would indicate. The better players shot from 3-point range during last season's summer league (minimum 20 attempts), the worse they shot come November. Accurate 2-point shooting also failed to translate, along with offensive rebounding, steals and even usage rate.
So there’s some hope for the rookie still. His summer league performance can’t be dismissed entirely, but the aspect of the game where he struggled is one that tends to have little to say about what happens between November and May.
There’s also this: Josh Selby appeared in 38 games for the Memphis Grizzlies in 2011-12 and 2012-13. He averaged 2.2 points on 33 percent shooting, 0.5 rebounds and 0.9 assists. In 2012, he was the MVP of the Las Vegas summer league.
So the summer league can tell us something. But it can’t tell us everything.