Celtics defense adapts for Kevin Durant and Kyrie Irving in Game 1

Game 1 of the series between the Brooklyn Nets was an absolute thriller, from the opening tip to the final sequence. It will likely go down as one of the more memorable playoff games in recent Celtics history, due both to the buzzer-beater from Jayson Tatum and the sensational shot-making from Boston villain Kyrie Irving.

Kyrie went off for 39 on really efficient shooting. Kevin Durant was less efficient (9-24 from the field) but still finished with 23 points. On a night where only one of the two was in the zone, they still combined for 62 — proving why the Nets are a dangerous threat regardless of the state of their role players.

Still, the afternoon was a winning formula for the Celtics on that end of the floor for many reasons. The pair combined for nine turnovers and had to earn everything they got. Boston’s defense was excellent.

Boston’s switch-everything defense, held together by a linchpin rim protector like Robert Williams, was the impetus behind their in-season turnaround that helped them seize the second-seed in the Eastern Conference. However, it also would be different with an injured Timelord, expose the C’s to mismatches that the Nets’ stars could exploit, and therefore play into the hands of Brooklyn’s best offensive threat: iso-ball.

How rigid would Ime Udoka be to what brought the C’s to prominence? Would he adjust at the start of the series, or save some of those tricks for later games to see if the switching could work at the outset? What we saw were three different types of coverages or rules that emerged in Game 1: a set of rules for Durant, a different set for Kyrie and an adjustment late-game that ultimately swung the result in Boston’s favor.

---

The Durant Rules

When Durant was involved in a ball screen with Al Horford or Daniel Theis defending the screener, the C’s would run drop coverage, sending Durant’s primary defender over the top and keeping the big close to the lane. The idea here was to prevent a switch, contest KD’s pull-ups from behind (which the C’s could do due to their length) and negate bigs like Andre Drummond from having a major impact on the offensive glass.

If the action was guard-to-guard, or didn’t involve Horford or Theis, the C’s would switch. With so many good perimeter defenders who could hold their own against Durant (pretty much everyone who played except Payton Pritchard), Udoka was fine switching those actions, which negated some of the typically impactful pick-and-pop actions the Nets go to with Seth Curry:

That applies to both on-ball and off-ball screens. When the Nets would go to a popular set of theirs, a post cross screen to get KD the ball on the right offensive mid-post, the C’s were ready, physical and all in-tuned to what the Nets were trying to do. Grant Williams accepted the switch on the cross screen, tried to deny Durant the ball, and even Horford chipped down physically to prevent the easy catch.

Grant deserves a ton of credit for how he guarded Durant all afternoon when they were matched up. He’s taking his role as a big wing stopper to heart, and the increased physicality of the playoffs suits him well. When he can come off the bench and rough up Durant for a few minutes at a time, the residual effect will only help Boston as the series moves on.

Grant clearly read the scouting report on Durant too, especially in how he thrives on feeling contact to get into his spin or fake-spin moves in the mid-range. When Durant was driving, you could see Williams pull the chair out from him to positive results.

Late in the game, even Horford tried his hand at switching onto Durant. This wasn’t an exceptional strategy, despite some positive possessions of staying in front by Big Al. The other Celtics, in anticipation of Durant’s quickness advantage, would help an extra half-step off their man. The result: open looks for guys who shouldn’t be getting them, mainly Kyrie, in clutch situations.

Brooklyn’s spacing on offense is immaculate. They put four shooters out there, spacing along the 3-point line to force rotations to be much farther, and one big along the baseline to keep a threat on the rim at all times. That’s the benefit of having two elite isolation players like the Nets do. Everyone else on the floor has a very simplified role.

Perhaps the guy who did the best job on Durant was Jayson Tatum, though. The Celtics’ MVP candidate has taken pride in defending and not just being a heavy-lifter offensively. His length and instincts are perfect for the assignment, and he came up with two huge second-half contests in isolation situations.

Generational scorers like Durant learn to adjust and adapt quickly. He’ll be ready for tricks like this from the Celtics and have a better, more cerebral game plan for how to attack Theis in Game 2.

---

The Irving Rules

In Game 1, Irving caught fire. The Celtics need more quickness on a guy like Kyrie to shut him off from getting deep penetration. That assignment requires discipline: not biting on jab and ball fakes, rarely lunging for the numerous dazzling dribble moves, staying attached through screening actions or handoffs.

Enter Marcus Smart, Boston’s lifeblood on the defensive end and now, Defensive Player of the Year. He drew the primary assignment on Irving, but would switch off with the other perimeter players when necessary. And he did an exceptional job all night of frustrating Irving one-on-one:

Boston went to the same strategy on Kyrie as they did with Durant: switch based on the C’s personnel, not on Brooklyn’s. If Theis or Horford set the screen, there would be no switch and the primary defender went over the top. We saw the C’s navigate both on the same possession against Kyrie, switching with two guards before fighting over the top with Theis’ man setting the screen:

What would happen if the Nets were able to force the switch and expose Their or Big Al to Kyrie? The rest of the team was ready, and would over-help proactively into driving lanes and force Irving to make skip passes. When Theis got switched onto Kyrie after a physical Nic Claxton screen, Derrick White was ready and closed the driving lane by jumping early off his man Seth Curry.

The result was an open jumper, but it was a 3-pointer from someone other than a Nets star and prevented a rim attack from occurring.

For the most part, the C’s did a good job protecting Theis and preventing him from getting exposed to the stars in isolation. It came at a cost, though. Irving was able to walk into many pull-up 3-pointers, a staple of his game.

The danger with drop coverage against a really good shooting big is that, if the offensive team sets the screen high enough, you’re giving up a 3-pointer to a high-level shooter. That’s what Kyrie got a fair amount:

They lived with the Kyrie buckets... for a while. While he was drilling jump shots in isolation, the troubling part about his points were the numerous blow-bys and easy layups he got. He drove around Tatum and Brown numerous times to the rim, and the Nets spaced the floor effectively to prevent help from impeding his layups:

The Celtics needed to adjust to Kyrie, and wound up doing so in the final minutes of the fourth quarter. Moving forward in the series, they may be best served to find ways to keep Smart attached to him for as long as possible. Smart does the best job on Irving of anyone on the team at shutting off those rim attempts, and the best anyone can do against a talent like Irving is to force him into being exclusively a jump shooter or a reversal passer.

---

The Late-Game Rules

The first 46 minutes of a game are an opportunity for your opponent to really get a feel for what you’re trying to accomplish. Change your tune in the final two minutes and you can catch your opponent off-balance. That’s what the Celtics did to the Nets on Sunday, saving an ace in the hole for the final two minutes by trying to different strategies: not switching guard-to-guard and trapping.

The non-switch was a moment between Smart and Durant, two high-IQ players, in a very deliberate action. The C’s had the matchup they wanted, with Smart on Kyrie and Tatum on Durant. After seeing Kyrie smoke Jayson a few possessions in a row earlier in the quarter, the two vets called off the switch and stayed with their original assignment. It’s hard to know if this was a designed change in the gameplan by Udoka or just feel between the two in a slow, deliberate action that they could communicate through.

Regardless of Kyrie’s difficult make, the idea of changing in the final minutes does and will keep the Nets on their toes.

Depending on which of the two superstars get going, the Celtics have the option to blitz them to get the ball out of their hands. On Sunday, that was Kyrie, and the C’s near-perfect last possession was indicative of how they can adjust to the hot hand.

Irving brought the ball up and was waiting for an isolation. Up a point, the Nets didn’t need to rush a shot, and bringing an extra defender by way of screen would only serve to bring a second defender into Irving’s space. The Celtics knew they couldn’t wait the entire possession with time ticking away, and didn’t expect a screen to ever arrive. They blitzed Kyrie right away, with Horford running at him with Marcus Smart as the primary defender to force the ball out of his hands.

The other three Celtics played a game of zones, identifying the other major threats, locking down the rim and preventing easy kickout options from presenting themselves. The result was a difficult (and well-contested) 3-pointer from Durant in the final seconds:

A storyline to watch as the series unfolds is whether the Celtics truly will embrace a switch-everything scheme with the likes of Durant and Irving. In Game 1, the script was clearly to avoid switching with Theis and, for the early parts of the game, with Horford. We’ll see if that holds moving forward, but the physicality of the Celtics and the individual defensive capabilities were all on full display in the series opener — even if Irving had a fantastic showing.