CelticsBlog film study: C’s defense starting to get crisp

Championship defenses aren’t built overnight.

Since Ime Udoka came to Boston this summer, he’s instituted sweeping changes to the Boston Celtics schematic approach to defense. The new head coach has taken the Celtics from a team that switches on occasion to a team that switches constantly and by design. It’s a different way to play and takes time to fully adapt to.

Early in the season, Boston has been better than I’d expect only ten games in. Most notably, they’re improving at a rapid pace, showing massive gains from a few early contests to where they’ve been over the last week. Ahead of last Saturday’s game against the Dallas Mavericks, Udoka had plenty of good things to say about Boston’s improvement on the defensive end and hit on both the techniques and intangibles of switching:

“The rotations behind [the defense] have really stepped up, us showing the crowd, shifting, keeping guys from the rim, and then everybody covering each other’s back. So when you watch the film you’ve seen over the last five games, we’ve been number eight in defense. Even in the games we lost, we played really well and just had some breakdowns offensively. So we feel good about it even in the losses, and then it just translated in those last two games. But the effort, understanding, and accountability with each other has been great in those games.”

The numbers back up Udoka’s claims of improvement and understanding. Boston gave up fewer than 80 points in two of their last three games, and held opponents to only 43% shooting during that span. So what is it that’s changed over that time to make the Celtics better? Discipline, communication and proper positioning. Nothing sexy, but all signs of mastery of their craft.

It’s important to remember that a great defensive possession rarely ends in a highlight. Instead, discipline and execution on that end result in long, stalled-out possessions where the offense takes a poor shot. In a switch-heavy system, where the point of attack is neutralized by the defensive exchange on a ball screen, the Celtics can shut off driving lanes and force those late-clock prayers. That’s where these Celtics thrive: they’re currently first in the NBA, with 12.9% of all defensive possessions resulting in a shot or turnover in the final four seconds of the clock.

The key to switching well enough to neutralize those threats of a ball screen or handoff comes down to the manner in which a defender accepts the ball. If he switches in a very passive manner, known as a soft switch, it’s really difficult to prevent the handler from turning the corner. A more aggressive switch, which at least makes the driver stop his momentum and pull back his dribble, is best. It’s important to remember: switching in itself doesn’t prevent dribble penetration, but timely switching does.

As the season goes on, the Celtics are becoming more comfortable with recognizing when a switch comes. Therefore, they can respond to switches more aggressively, getting out to prevent the ball from turning the corner. The result: a lot of stalled-out possessions.

Udoka has been patient with his approach, knowing that the Celtics won’t be perfect overnight and the players are still adjusting to his requirements. That perspective allows him to be comfortable with the growing pains and recognize their gains.

“Some things that we were asking them to do early were probably not natural for all of them, so we knew it was going to take some time,” Udoka said prior to Saturday’s game against the Dallas Mavericks. “But you just gotta keep working.”

When the Celtics are engaged and on top of their switching, they’re so difficult to get past one-on-one. Switching at the right time prevents opponents from generating a paint touch at all, instead passing back and forth away from the hoop. You can see how bad opposing offenses look when they can’t generate a single paint touch:

The next conquest for the Celtics to master: knowing when not to switch. “We don’t need to switch on certain things, and they’re getting a better understanding of that,” quipped Udoka on Saturday. When the Celtics can stay with the right matchups, especially late-clock, they throw a massive curveball to the offense when they have no time to react accordingly.

Watch the possession below. Al Horford and Aaron Nesmith are involved in a late-clock ball screen. The screener slips the screen, a calculated move by Miami to attack switches. Instead of falling into the trap and letting the roller be open, the Celtics avoid any dilemma by staying with their assignment. The wise Horford recognizes the slip, Nesmith stays with his man and Marcus Smart comes out of the corner to provide relief.

Defense is always a work-in-progress under a new coach. Philosophies, terminology and overall schemes change. Udoka swears to be dedicated to a team-based defense, and the early returns on the switching style show that the Celtics are buying in as a group. It’s early, and they’ll keep getting better. It’s clear they’re already pretty good at this.