HOUSTON — Some nights in the NBA, you can plan a game, study film, then on the court discover a simple truth: Nothing is working.

And for much of Monday night, that’s where the Knicks found themselves. There was a key ingredient missing from the revamped offense that had begun to flow so smoothly in recent games: the ability to make a shot. Layups echoed off the backboard. Mid-range shots flew off the rim. The Knicks repeatedly fell into double-digit deficits as the Rockets’ athletic team bullied and blew them away on the other end.

But if you want to be the contending team the Knicks believe they can be, you find a way. And through trouble and frustration, they managed to get within reach. They withstood a nightmarish shooting performance (23-for-62 inside the arc) to have chances to tie the score in the final minutes. Instead, they found themselves stuck in the clutch, as they had been much of the night.

The Knicks fell 109-97, dropping to 3-3 on the season with one extra stop on their four-game road trip. Only OG Anunoby seemed to be on his game, shooting 7 of 14 for 21 points. He was 5-for-6 from three-point range. Jalen Brunson led the Knicks with 29 points, but shot just 9 of 24 from the floor. Deuce McBride went 0 for 9 – 0 for 5 from three. Karl-Anthony Towns finished with 17 points and 19 rebounds despite struggling with foul trouble much of the night. Towns’ foul trouble made defending Alperin Sengun nearly impossible as the Rockets center scored an efficient 25 points on 11-of-15 shooting.

The key idea for the Rockets wasn’t so much the scoring as the defense of Dillon Brooks, who frustrated almost every Knicks player as he switched from Towns to Brunson and almost everyone in between.

The Knicks knew this was coming. Josh Hart had warned a day earlier. “I think he’s a good defender. We’re going to try to be physical, we’ve got to make sure we set good screens.

A pair of Brunson free throws with 5:28 left cut the deficit to one, as close as the Knicks had been since the first quarter. But Sengun scored in the paint as he did for much of the evening. This time it was Josh Hart responding with a layup. Sengun increased it again to three and Towns missed his shot from three. Jalen Green then beat the 24-second clock with a three to extend the lead to six.

“He’s tough. He’s so crafty,” Knicks coach Tom Thibodeau said of Sengun’s defense. “Multiple fakes, good touch and can play away from the basket. (He’s) deceptive, changes speed and knows how to create space to shoot. So you have to be disciplined, stay on the floor, be the second jumper and then we have to be active in our reads in terms of helping.

“We also have to keep him with our team. He can put the ball in the basket but he’s also a very good passer. So if you lose vision outside of the game, he can make you pay with his passes, especially on the ground. So (you have to) be aware of what’s happening on the ground and stay disciplined with it.

The Knicks continued to fight back, Mikal Bridges nailed a corner three with 3:03 left and the lead was only 98-95. Anunoby smothered a Tari Eason drive and the Rockets were booked for a 24-second violation. Once again, the Knicks couldn’t take advantage of Brunson missing a jumper and Eason finishing a break at the other end to extend the lead to five.

Hart cut the lead to three with a layup off a nice pass from Brunson, but Amen Thompson caught a pass in the air, faking a pass and in the same motion slammed in an uncontested dunk with 1:34 to play. Brunson missed a three and Green launched the dagger, a three-pointer with 58.1 seconds left for a 105-97 Rockets lead.

The Rockets shut down the Knicks’ offense, putting defensive stopper Brooks, their 6-foot-6 wing, on Towns to start the game. And when he finished banging, grabbing and frustrating Towns, he moved to defend Brunson. While the Knicks were angry at the referee – Josh Hart being hit by a technical problem and a number of other players appearing to walk the tightrope and barely avoiding one – Houston built up a lead of up to 15 points.

But the Knicks managed to stay in the game, trailing just 61-56 at halftime, thanks to OG Anunoby’s 16 points on 4-of-4 shooting from three.

Towns was called for his fourth foul just 94 seconds into the second half, but Thibodeau opted to keep him on the floor and he grabbed 10 rebounds in the period, untracked. But the Knicks still feel behind by 13 points and fighting to climb out of a hole as they struggle to find their offense.

Notes and quotes: Cam Payne was held out with a hamstring injury. … The Knicks haven’t made it official, but sources have confirmed the team is converting rookie Ariel Hukporti from a two-way contract to a standard contract and signing free agent Matt Ryan. The team must have 14 players on the roster by Tuesday, but in the meantime it has the option to prorate contracts, keeping them below the second apron of the salary cap. The 6-7 Westchester native shot 45.1% last season from three for New Orleans and has shot 41.1% in his three seasons.

Steve Popper covers the Knicks for Newsday. He spent nearly three decades covering the Knicks and NBA, as well as nearly every sports team in the New York metropolitan area.