For the most part, the zone defense in NBA basketball is a lukewarm strategy that can't be effective if deployed on a long-term basis.
No team adheres to it for 48 minutes, and a majority turn their noses up at utilizing it at all. But in recent years, the zone has been more effective when thrown at offenses in small doses.
On their surface, the Boston Celtics used to be one of the many organizations that snobbishly (and correctly) preferred to contain the ball with brick-wall man-to-man defense. But over the course of their last four games, they've harnessed the zone for major minutes—and have seen major success by doing so.
In an 82-game season long enough to exhaust even the most well-conditioned athletes, zone defense can be a useful ally. Especially when your thin, aging team has a few players who are more useful on the defensive end as part of one interlocking system rather than as singular parts (hello Jordan Crawford and Jason Terry!).
The sample size here is obviously minuscule, and it's not as if the Celtics played a true zone for 48 minutes, but there's something to be said for the way their defense has operated before last night's blowout against the Charlotte Bobcats—and how blatantly effective it was to the naked eye. Here are a few interesting numbers to take away.
Since they really went strong with their zone against the Philadelphia 76ers five games ago (they also used it against the Golden State Warriors on March 1st, but to a much lesser extent), Boston is holding opposing teams to 41.6-percent shooting from the floor, which is the third-best mark in the league over that span, according to NBA.com/Stats. Opponents also just shot 26.4 percent from behind the three-point line; only the Memphis Grizzlies were stingier.
Opponents are shooting 55.1 percent in the restricted area (seventh best in the league) despite Boston allowing the most attempts there out of anyone (having the Indiana Pacers and Oklahoma City Thunder as two of your four opponents will certainly see to that).
Defending the corner three, Boston held the Sixers, Pacers, Thunder and Atlanta Hawks to just 30.4-percent shooting, good for fourth-best in the league.
Here are a few clips from the past few games that show just how effective Boston's zone defense has been. Pay close attention to Terry, who's the primary reason Boston goes to this scheme in an attempt to slow down penetration from the perimeter.
Here we see the Celtics passing off the ball-handler along the perimeter, from Crawford to Terry then back to Crawford. Kevin Garnett roams below, offering help for Courtney Lee as he attempts to front Paul George in the post, while rotating back to cover his man, Ian Mahinmi, who isn't a threat from the perimeter. Jeff Green, guarding Tyler Hansbrough, checks Mahinmi while Garnett is out of the area.
The possession ends with Mahinmi launching a 20-foot jumper; exactly what the Celtics wanted.
Here the Celtics have Chris Wilcox and Jeff Green switch assignments on the perimeter once Dorell Wright and Arnett Moultrie run a pick-and-roll. Wilcox drops down to double when Wright enters the ball to Thaddeus Young in the post, but then has to immediately close out after Wright receives a kick-back pass behind the three-point line.
These aren't traditional zone schemes that the Celtics are running, but the bottom line is that they're working.
Don't expect to see the Celtics heavily utilize it in the postseason, but for now it's getting the job done.