The Knicks are becoming a third quarter team. It’s a good thing because it shows they are capable of responding to adversity with the appropriate level of desperation.

It’s a hindrance, however, because this team has become comfortable with sleep-walking through opening quarters and halves, because — well — because they can turn it on and string stops together, turning defense into offense on a moment’s notice.

But it doesn’t work like that. Not at this level.

Flipping a switch is a luxury reserved for teams that have been there and done that already, and even then, believing that you can, again, because you have before is a slippery slope.

The Knicks have neither been there nor done that. Which is why they are playing with fire with two key players out due to injury.

The flames were evident in Tuesday’s matchup against the Dallas Mavericks — the second leg of a back-to-back for the Movs and the first of two games in two nights for the Knicks.

The Mavericks are a team battered by injuries to both Kyrie Irving (torn ACL) and Anthony Davis and scrambling in the aftermath of the Luka Doncic trade. Yet they still have a puncher’s chance at making the playoffs, just a game behind the 10th-seeded Phoenix Suns.

So the Mavericks came to play early Tuesday night. The Knicks — as has been the case at times with Jalen Brunson (right ankle sprain) out of the rotation — did not.

The result was too close for comfort through the first two quarters, a tie-game at halftime before the Knicks went on a furious second-half run to pull away with a 128-113 victory over the Mavericks at home.

New York outscored Dallas, 30-16, in the third quarter and 30-29 in the fourth. In doing so, the Knicks snapped free from a nasty spell of poor performances against NBA Draft Lottery-bound opponents.

But the games within the game were concerning, at least to start.

Only a week ago, the Knicks took one of their most disappointing losses of the season to a San Antonio Spurs team without three key fixtures: franchise cornerstone Victor Wembanyama, All-NBA guard De’Aaron Fox, and Hall of Fame head coach Gregg Popovich.

n their absence, it was Sandro Mamukelashvili who put forth the perfect 19-minute game: a career-high 34 points on 13-of-14 shooting from the field and 7-of-7 shooting from downtown.

The Knicks went on to lose, 120-105.

It took them another two quarters, another all-time performance from an opposing rotation player, and a tied game at the half against the Western Conference’s No. 11 seed for New York to wake up and rise to the occasion on Tuesday.

This time, it was Atlantic City native Naji Marshall who made 13 of his first 15 shots. Marshall had 28 points by the halftime break. He would go on to finish with 38 points on 13-of-25 shooting from the field. Another career-high for an opposing player on a losing team.

“We didn’t start the game like we’re supposed to with energy and physicality,” said Josh Hart in his walk-off interview. “We knew we had to pick it up from the first half.”

So the Knicks got to work in the third quarter. It’s a trend that’s become common in recent weeks. After two underwhelming quarters against the Washington Wizards, New York blew the game open by winning the third period, 35-26. They outscored the Spurs, 29-16, in the third quarter after losing the first half by 24. And they showed some signs of life in the third quarter of their loss to the Charlotte Hornets — the second leg of a back-to-back and the seventh stop in a stretch of seven road trips in eight games.

What’s clear is coming to life in the second half is an unsustainable pathway to victory, even if it worked on Tuesday against the Mavericks.

If the Knicks want to become a 48-minutes basketball team, they can’t start the clock midway through.

Anunoby finished with a team-high 35 points on 15-of-24 shooting from the field. Karl-Anthony Towns added 26 pints, 12 rebounds and 11 assists, and Josh Hart added another 16 points, 12 rebounds and 11 assists. The two became the first pair of Knicks teammates in franchise history to record triple-doubles in the same game and Hart surpassed Walt Clyde Frazier as the all-time franchise triple-double leader with nine on Tuesday night.

“Just blessings. We have a great group of guys,” Hart. “To do it here at MSG, it’s just a blessing to do it in front of these fans.”

Anunoby logged 38 minutes, Bridges and Towns logged 34 apiece and Hart played 33. The Knicks will now face the Los Angeles Clippers in the second leg of a back-to-back on Wednesday.

The Clippers enter Wednesday’s matchup winners of eight of their last 10 games. If the Knicks take too long to wake up, L.A. will make them pay.