In Game 1, shooting luck fell in Boston’s favor, but its offensive execution seemed to earn it. But just look at the distribution of assisted field goals in Game 4, courtesy of NBAViz. The Raptors are finding ways to create good 3-point looks for each other or hit their rolling bigs in ways the Celtics can’t even compare.
Boston actually executed well defensively for much of the Raptors’ 32-point third quarter, generally surviving Kyle Lowry’s best period of the night. But there were moments like the one after Daniel Theis survived a “veer” onto Fred VanVleet, shutting down the play until he failed to box out O.G. Anunoby, who grabbed the missed 3-point attempt and threw it down. Then Rob Williams entered the game.
The Raptors know that Williams can shut down the first action in front of him, but he can be overwhelmed by the required persistence and awareness to shut down a 24-second possession. So they attacked him in high pick-and-rolls, getting VanVleet a headstart to get downhill. The Celtics were
stealing a page from the Raptors’ playbook and “pinching” in on VanVleet with the weak-side elbow defender.
What better way for one grandmaster to try to take down another than by using his enemy’s own strategy against him? The risk, of course, is that the target has seen opponents attack him countless times and he knows which of their approaches works. So Nurse turned VanVleet into Steph Curry.
As Grant Williams sunk in on the drive, VanVleet kicked it out to Lowry positioned out on that elbow. Kemba Walker was guarding VanVleet and left him to contest what he expected to be a Lowry shot. Williams, whose job was to pinch and then recover, did the same thing. As they were duplicating their closeouts toward the sideline, VanVleet relocated nearby and Lowry swung it to him against the momentum of the defenders. Williams did an admirable job to turn back again and contest, the defensive equivalent to running suicides. But the defense was already dead.
On the next play, the Celtics tried to “ice” a Lowry pick-and-roll, but Serge Ibaka never set the screen, Brad Wanamaker and Williams just went where Lowry wanted them and Ibaka ended up with a wide-open 3. VanVleet followed it with another pick-and-roll flowing into a give-and-go with Lowry, where this time Walker just forgot about his man, VanVleet, after the ball left his hands. Toronto had blown open its biggest lead, and Stevens had to make a change.
Marcus Smart came in for Walker and the Celtics started switching perimeter actions. The difference was apparent right away, as Toronto couldn’t lose anyone on the perimeter and the Celtics weren’t caught in rotation underneath. The Celtics were still constantly losing the ball or running sloppy actions on the other end, but they were getting some stops and the potential to seize momentum was there.
“Missed some free throws, missed some 3s, but we’re right there,” Stevens told TNT’s Allie LaForce after the third quarter. “We’ve got to play a little bit better to start this quarter to give ourselves a chance. But we were here a couple games ago, so we’ve been here before.”
As Stevens’ answer finished playing on the broadcast, Jaylen Brown attacked through traffic to get to the line just as Stevens explained how Toronto mixes up its defensive structure to move the big around. Toronto was in a Box-and-1 on Jayson Tatum, blocking him from running
his go-to “Stack” play after he carved through the Raptors’ defense in the third quarter.
On the other end, Pascal Siakam posted up Tatum and the Celtics wing defended him perfectly into a tightly contested fadeaway. But Tatum was called for a phantom foul, which triggered him to run down the floor in disbelief. While it may have been karmic justice for an erroneous foul call on Siakam guarding Tatum in transition earlier in the game, the Celtics star was clearly pressing on offense and seemed to lose the ball every other possession in the fourth quarter.
But the switches were working. Grant Williams was stepping up and taking on Toronto’s guards, who were just coming after him possession after possession. He got five stops in six possessions over the next several minutes, with the only bucket being a well-defended Lowry isolation step-back that nobody could have stopped.
Then Nurse found his countermove. He has been trying to find a balance between running straight-up pick-and-roll with his point guards with side-to-side actions in the fourth quarters of this series. With the Celtics switching everything so that they could keep the ball in front of them, Nurse went back to big looping handoff actions to make the Celtics switch at high speed.
Follow VanVleet’s path through this play after the ball leaves his hands, as he tries to draw a giant smiley face. VanVleet passes the ball on the right side, runs in a giant loop around the frontcourt, then emerges for a ball screen for Lowry on the other end. Walker is chasing him and then has to switch onto Lowry with his hips open to the middle, allowing Lowry to spin off him and get a headstart into the paint.
Before this action, it was perplexing why Siakam and Ibaka were standing shoulder to shoulder in the weak-side corner, a formation that seemingly never exists in the NBA. But as Lowry advanced and Grant Williams had to step into the lane, Ibaka quietly tiptoed behind Brown, who was too focused on Siakam to remember Ibaka was just over his shoulder. Once Ibaka got past him, the play was over.
Boston was able to stay in its switch scheme for a little while longer because Toronto kept putting the ball in Norm Powell or Siakam’s hands, which in this series has meant that the play was going nowhere. But the Raptors were able to run one post-up for Siakam on Brown, who no longer could defend Siakam physically because he was in foul trouble and surrendered a post jumper. Then Grant Williams picked up Powell on a switch and ate him alive, but Ibaka hard rolled with Walker desperately fighting to stop him and was able to catch the rebound and lay it in easily.
It became clear that Ibaka and Siakam were going to kill Boston at the rim if the Celtics didn’t get big and stick to their matchups, so Stevens brought Theis back in for Williams. The Celtics were now going to change their scheme from switch and stick to switch and kickout. This meant that instead of just switching screens and staying with your new assignment, Walker, specifically, was going to switch screens and then a nearby teammate would tag team in for him onto the big man and he would sprint out to the weak side to find another guard to cover. The Celtics have used the scram switch frequently against bigs, where they would do this during the entry pass to the big. But Boston was using a kickout switch to just do this preemptively.
Smart truly showed his versatility on these plays, picking up Siakam and once again shutting him down. But watch how Boston used a delayed double-team akin to its scheme against Joel Embiid from a few weeks ago, before the Celtics did not corral the loose rebound. This happened several times in the final minutes, perhaps the big separator in the end when they were keeping it a two-possession game. That should have been a stop, but instead, Toronto used a rare double pindown screen on the inbounder to stall Tatum in his chase of Lowry to get its star guard an open 3. Boston could have made it a one-possession game if it had grabbed the rebound. Now it was an eight-point game with less than five minutes left.