Lessons of the 24-second shot clock
By Rob Mahoney
There are innumerable variables to account for when it comes to analyzing basketball performance. But among those factors is a single, static force that lingers in the background of every single offensive possession, subtly dictating its terms: the shot clock. NBA teams have 24 seconds at a time to go about their scoring business, and all of their primary actions are designed to generate a shot within that designated span. Those on the court are taught to be fully aware of the clock, and fully cognizant of how its marching countdown will bring the walls in around their offensive efforts.
As such, it’s worth investigating the relationship that this often overlooked element of the game has with specific teams, especially considering that each NBA squad uses the clock in its own unique way. Below are observations drawn from the data available at 82games.com, which dissects performance against the shot clock (separated by intervals: 0-10 seconds passed, 11-15, 16-20, 21+) in terms of percentage of a team’s overall attempts, effective field goal percentage (eFG%), and percentage of field goals assisted.
• The Clippers’ offense goes polar. The Clippers are packaged as Showtime reincarnate while essentially playing at a league-average pace. On the surface, that may seem like a clear discrepancy, a misunderstanding born of highlight-fodder fast breaks. Yet those two descriptions bear no contradiction nor any bit of mutual exclusivity. The Clips are indeed a committed transition team, but manage to balance out their overall pace with a heavy dose of late-clock attempts. No other team’s shot distribution is as stilted toward the shot clock’s extremes, in part because L.A. has both the personnel to push the break and an endlessly patient creator through which to funnel most offensive possessions. Chris Paul possesses an uncommon restraint for a player with his speed and skills, in part because of his preternatural court awareness. Every movement on the hardwood and tick off the clock is a part of his complete picture of the game’s action. It’s for this reason that Paul is considered the game’s preeminent point guard, regardless of any measure of assists or quantification of playmaking. He simply views the game and operates on the floor in a way that’s fundamentally different from every other player in the league, thereby making him and his team somewhat immune to the tension that builds as his live dribble brings the shot clock to its final gasp.
• The Spurs roll into their offense seamlessly. On the other end of the spectrum are the tried-and-true Spurs, who have been the NBA’s most lethally efficient team to date when it comes to working through the body of the shot clock. The initial transition push is crucial for San Antonio, but where the Spurs really excel is in the quick initiation of their half-court offense. There’s no hiccup between rebuffed fast break and slow-down set; Tony Parker or Manu Ginobili merely dribble back out to the perimeter and immediately trigger the progressions of their half-court offense. As a result, they posted truly impressive shooting marks (as measured by effective field goal percentage) from 11-20 seconds into a given possession — just after the secondary break has come and gone but notably before the late-possession panic sets in. They’ve been particularly dominant in the 11-15 second range, in which their advantage over the second-place team (Houston) in eFG% is equivalent to the gap between second and 10th (Golden State).
• The Warriors do their work early. Golden State’s fast-breaking disposition seems to carry throughout the entirety of a given possession, as evidenced by the fact that the Warriors attempted the lowest percentage of their overall field goals in the final four seconds of the shot clock. Just to put things in perspective: Golden State has created so many early shots that late-clock shots account for just 10 percent of their overall attempts — roughly half of the attempts of the more deliberate offenses in Memphis, New Orleans and Brooklyn.
• When it comes to late-clock shot-making, two teams stand apart. There are few things in basketball more excruciating for a defense than a made basket at the tail end of the shot clock, as some 20-odd seconds of well-executed denials can be undone by a single player making a difficult shot. Great offensive teams need both bailout artists and offensive diligence, and success during this range of the clock at least loosely correlates with both.
When it comes to this specific area of offensive performance, two teams stand well above the rest of the field: the Lakers (.522 eFG% in the last four seconds of the shot clock) and the Heat (.511). Neither stands as all that much of a surprise, given that both teams’ offenses revolve around some of the best individual shot creators in the game. In this regard, Bryant is as good as would be expected: his individual eFG% at the end of the clock is .568, which is an incredible mark when we also consider that defenses expect him to take those very shots. Metta World Peace (.560) and Steve Nash (.667) also help anchor the Lakers’ high overall percentage, largely by way of spot-up three-point shooting after other offensive options break down.
Miami follows a similar blueprint, in that a single star (LeBron James, .578) takes a ton of the attempts in this particular situation, and is flanked in efficiency by perimeter shooters. Shane Battier (.533) and Ray Allen (.527) fill that complementary role for the Heat, though Bosh’s deadeye mid-range shooting (.481) is helpful if not entirely as efficient.
• Two lesser teams fare unexpectedly well while working against the clock. One would expect the league’s most efficient teams at the end of the shot clock to all rely on strong isolation players, and to some extent that’s true. As noted above, L.A. and Miami are far and away the NBA’s best in this particular measure, and behind them are the Carmelo Anthony-powered Knicks. Yet coming in at fourth and sixth in the rankings, respectively, are the 76ers and the Suns — two outfits with neither star-level iso scorers nor high-functioning offense in general. Philadelphia seems to balance out its lack of individual creators with a ton of assists on those possessions, but Phoenix’s late-clock scores go largely unassisted. Jared Dudley, Marcin Gortat and Goran Dragic are the biggest contributors to the Suns’ high effective field percentage, though there doesn’t seem to be any specific method or reason behind their lofty ranking. A round of applause unto Phoenix for defying the odds and logic itself.
• Houston doesn’t pass up good looks. The Rockets’ shot selection is pretty close to the analytical ideal in that Houston aims to create looks at the rim and behind the three-point line without much regard for mid-range jumpers. That in itself helps to explain why a team so inexperienced currently boasts a top-10 offense, but Houston’s clock usage more or less confirms that their style is something of a strategic mandate. Commentators everywhere frown on a player who attempts a three-pointer early in the shot clock, but for Houston an open shot is an open shot. As a result, a league-high 70 percent of the Rockets’ field goal attempts come in the first 15 seconds of the shot clock, all due to an approach that encourages uptempo execution and the capitalization on the first quality look available.
Data reflects games through January 7th.