Using the Shot Clock as a Sixth Defender
By Seth Partnow
Dec 26, 2014; Atlanta, GA, USA; Milwaukee Bucks guard Giannis Antetokounmpo (34) is defended by Atlanta Hawks forward DeMarre Carroll (5) and forward Paul Millsap (4) in the first quarter at Philips Arena. Mandatory Credit: Brett Davis-USA TODAY Sports
Early offense is great. Usually it entails wide open looks shots off defensive breakdowns, fast breaks or put backs from offensive rebounds. Similarly, late clock offense is much harder; defenders are intuitively aware of how the shortened time horizon has shrunk the range of options greatly, allowing for much heavier defense on the impending shot. A natural extension of these truisms is longer defensive possessions tend to reflect better defense. Certainly, upon causal viewing, it is noticeable when one team is consistently trying to create looks against the shot clock. They aren’t getting anything easy, with the first several options in a given set shut down or at least defended well enough to dissuade a shot.
In this way, pace is the first line of battle between O and D. Attacking the defense before it is set results in good possessions, denying those initial forays requires the offense to dig deeper into less favored areas of its arsenal. At the other end of the shot clock, is there anything more demoralizing to a squad’s defensive ethic than playing 21 seconds of hard defense rewarded by…the opposition springing open for a layup with two seconds remaining on the shot clock?
As with most things, there is a wide variation between NBA teams in terms of both their ability to force late shots, their ability to defend early attempts and so forth. But much like the splits between assisted and unassisted shooting, every team in the league is better late in than early:
Best of all is, of course, forcing very late shots, as those taken with four seconds or less on the shot clock are the least efficient at all. On the whole, NBA teams force these very late possessions 11.9% of the time. One team this season has been by far the most proficient at forcing these desperation possessions:
To some degree this indicates how a team without much in the way of rim protection or a flashy trapping scheme can rate as the 4th best defense in the NBA to date.[1. per Nylon Calculus efficiency ratings] Aligning with observation, the defense is simply locked in, shadowing opposition sets as well as any team in the league.
As a final data point, this shot clock data confirms just how much “the game slows down” in the playoffs.
If these time splits numbers hold up and translate on a team level to the postseason, this slower pace is an advantage for teams best able to “close out possessions” which thus far this season are in order of best-to-worst Oklahoma City, Chicago, Golden State, Houston and Phoenix. On the other hand, this is yet another area of concern for the floundering Cavs, second worst (prior to Thursday’s contest in Los Angeles) in the league to the Knicks, allowing 48.1% eFG late in the shot clock, after playing only marginally below average field goal defense for the first 16 seconds of the shot clock.