After last night’s 92-88 win over the Warriors, the Celtics’ defensive rating is a suffocating 97.2. The last time we saw this team approach this level of defensive dominance was during the reign of the Big Three, when Boston won the 2007-08 championship with a defensive rating of 98.9.
The league has changed a lot since then, and the objective pursued by this current Celtics defense is accordingly different, and perhaps more difficult to attain, then what the ‘07-08 team was after. That championship team’s defense, anchored by Kevin Garnett, Kendrick Perkins, and James Posey, was designed to prevent LeBron James from rampaging to the rim whenever he wanted to. James was the finest battering ram the league had ever seen, and the Celtics aimed to be the one fortress he couldn’t crack.
NBA defenses worry less about blunt force trauma today and more being stretched and torn. The ideal NBA offense, as mastered by the Warriors over the last few seasons, sends defenses scrambling with a never-ending stream of pick-and-rolls, weak-side action, and ball movement. To defend the Warriors a team has to be able to switch everything, stop multiple pick-and-rolls per possession, and run like hell to keep the team’s shooters off the three-point line. You need a swarm, and you need the swarm to be disciplined.
That’s what the Celtics were last night, particularly during a third-quarter stretch that all but decided the game. The Warriors have been blowing teams out in the third quarter this season, and were on track to do the same to the Celtics. With just under five minutes left to play in the third, the Warriors were up 66-49, and that’s when Boston’s defense locked in.
For the next five minutes, the Warriors were denied both space and oxygen. Missed shots were followed by turnovers and then more missed shots, and by the end of the quarter the score was tied at 68. The Celtics were playing such furious defense that it almost looked like they had six men on the court. Watch how Marcus Smart comes out of nowhere here, like a defensive back reading the quarterback for a pick-six:
Here’s a possession in which a few Steph Curry crossovers are easily repelled, followed by Marcus Smart teleporting to the baseline to close off a wide open lane in front of Andre Iguodala:
And here are the Celtics using their ability to fight through screens, switch, and recover to reduce what is almost always deadly offensive action to impotent sputtering:
Whenever a defensively sound team manages to contain a high-powered offense and win a low-scoring game, there’s an impulse to label the contest a “rock fight,” or some other adjective meant to evoke the image of one gritty, hardscrabble team putting some bruises on their more skilled opponents. That’s not what happened last night, though, because a team that spaces the floor and moves the ball like the Warriors do can’t just be battered by a rock. Containing the Warriors’ offense requires just as much skill and synchronization as it does to produce such an offense. The Warriors thrive by moving themselves and the ball until their opponent’s seams start to tear, but when a team can move with them and cover the floor like the Celtics did last night, there are no seams to pick at. It’s a fair fight.