Analytics drive Houston’s style, but its Game 4 victory at Oracle Arena was aided by old-school grit. Rockets forward P.J. Tucker said afterward that the team came into Game 4 with a simple plan: “Let’s get [the Warriors] uncomfortable today.” Mission accomplished. The Rockets defense flustered Golden State en route to a 95-92 win that ties the Western Conference finals at 2-2.

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Led by Tucker and Trevor Ariza, the Rockets defense was über-aggressive on the perimeter, which pushed the Warriors’ actions farther away from the arc. Houston didn’t just play harder in posting a stellar 96.7 defensive rating, though. It adjusted its strategy to be more selective with switching screens, which deterred the Warriors from scoring easily off of their deceptive cuts.

There’s a lot happening here, like there is on so many Warriors possessions, but the Rockets respond perfectly by switching and helping when they need to—like Tucker sliding into the paint on Draymond Green’s roll to the rim—and staying home other times—like when Ariza stuck to Stephen Curry and blocked his 3. “We stuck our nose into the dirt,” Ariza said. “When our defense is locked in on a string, we’re a really good team.”

Communication is critical to playing connected defense, and it was clear even while the Warriors made their mini-runs that the Rockets were prepared for what was coming.

Previously in the series, the Rockets probably would’ve switched this slip screen, and Klay Thompson would’ve laid the ball up at the rim. But this time, the Rockets resisted. As Thompson positioned to screen for Kevin Durant, Eric Gordon stayed between Thompson and the rim. For whatever reason Thompson decided to attack, and the Rockets will live with that. “We just tried to not give into the switching all the time,” Ariza said. “Sometimes they don’t come together and actually screen. We were aware of that.”

Here it is again later in the game, but Durant slices to the 3-point arc rather than diving to the rim like Thompson did. I asked Ariza if it was a point of emphasis during their off day to avoiding switching everything, and he nodded, smirked, and raised his eyebrows. “Right. Yeah,” Ariza said. “A lot of film.”

It looks simple, but it’s not easy to defend the Warriors’ fancy off-ball actions. They’re deceiving, but it’s not unpredictable as long as a team is prepared and communicating. They’ve seen it before.

This play from Game 3 features Curry dancing around before cutting to the rim for an open layup. Gordon switches with Ariza instead of keeping his body between Curry and the rim, so the paint was open. There was no chance for Ariza to catch up, and even if Curry had been covered, Andre Iguodala would’ve been open.

Iguodala missed Game 4 with a knee injury, which undoubtedly hurt Golden State. But his presence wouldn’t have changed the fact Houston was flat-out better on defense thanks to constant chatter, either vocal or through hand signals to their teammates around the floor. “We have to communicate and stay locked in,” Rockets center Clint Capela said after the game. “We were more aware and more aggressive.”

The Rockets entered the series with a strong game plan. Even when the Warriors were rolling, it never felt super easy for them. They’ve been forced into more isolations than they’ve run all season, and frankly there’s nothing any defense can do about Durant shooting over defenders, or Curry launching from 35 feet. “It’s not like we have a magic formula,” Rockets coach Mike D’Antoni said after the game. “They’re going to make their runs. There’s nothing you can do about it. The idea is to keep attacking.”

The tweaks to switching screens were vital, and so was their extra effort. After withstanding a torrential run by Curry during the third quarter—in which Curry scored 17 of his 28 points (he was a pedestrian 10-for-26 shooting on the night)—the Rockets turned it up a notch to open the fourth quarter to kick-start their comeback.

During Golden State’s second possession of the final frame, Warriors center Jordan Bell began setting a down screen to spring Curry open. The Rockets switched Capela onto Curry, and the big man aggressively denied the actions by stretching out his arms to push Curry to the logo.

Curry didn’t have the freedom to turn the corner for a 3, and then the entire defense locked in for the remainder of the possession. Paul zoned off his man to stop Curry’s drive left, and Gordon gave Bell no respect as the rookie spotted up in the corner. Capela closed the deal by using his 7-foot-5 wingspan to swat Curry’s layup out of bounds.

After the Warriors inbounded the ball, Tucker perfectly timed his double to strip the ball. “We just gotta be smart. It was a heads-up play,” said Tucker, who logged a game-high 16 rebounds, along with two steals and one block. “You try to get the edge and all night we made those types of plays.”

After falling down 12-0 to open the game, then trailing by 10 to start the fourth quarter, the Rockets easily could’ve folded, especially after getting smoked by 41 points in Game 3, but they grinded and held the Warriors to a season-low 14 assists while forcing 16 turnovers. “Mental toughness is just as important as physical toughness,” Paul said after the game. “And I think guys on our team showed that tonight.”

The Rockets defense held the fort, and they got offensive contributions when they needed them. James Harden carried the offense in the first half, and then Chris Paul did in the second half, as others chipped in along the way. The backcourt duo finished with a combined 57 points and also played competitive defense. Tucker and Ariza played their best games of the series, but the team peaks when everybody on the roster battles through every screen and locks in. “This is the highest level we’ve ever played defensively, without a doubt,” D’Antoni said. “[The Warriors] got a little tired in the fourth quarter, and that’s because they felt us for three quarters.”

It can sometimes feel like no matter what a team does, it’s never enough against the Warriors. But the Rockets have the versatile personnel to make life hard on the Warriors. They’ll need to match their intense effort when the series returns to Houston for Thursday’s Game 5. “It’s go time. This is it. We’ve been talking all year about wanting to be in this position,” Tucker said. “We ain’t done yet. It’s not time to reflect. It’s time to keep moving forward.”