DALLAS – Because they were fanatical about finally playing some rock ‘em, sock ‘em defense, the Dallas Mavericks were able to stand tall Tuesday night while waving goodbye to their six-game losing streak.

With defenders going all-out and helping each other all over the American Airlines Center floor, the Mavs punched the Washington Wizards in the mouth first and wound up landing an impressive 119-100 victory before a sellout crowd of 19,234. The win boosted the Mavs’ record to 3-7 going into the second leg of a back-to-back Wednesday night at 8 CT in Utah.

The 100 points the Mavs allowed were the fewest an opponent has scored this season as Dallas beat Washington for the 16th time in its last 17 meetings. And the win helped the Mavs get that very salty taste out of their mouth after they were roughed up at home last Friday while losing to the lowly New York Knicks.

This was the Mavs’ first win since Oct. 22 when they defeated the Chicago Bulls, 115-109. And it came at an opportune time, since four of the Mavs’ next five games are against teams that qualified for the playoffs last year.

“It’s been a long time since we won a game,” coach Rick Carlisle said. “It feels good to win.

“Quick turnaround. Not much rest, but we’re looking forward to getting back out there tomorrow.”

For a change, the Mavs played role reversal while jumping out to a 35-24 lead after the first quarter and setting the tone on what kind of night this was going to be. With Wesley Matthews blazing hot from long distance, the Mavs methodically mounted a 58-34 lead with 5:33 remaining in the first half.

The Mavs’ lead settled at a whopping 70-49 at the half and was their highest-scoring first half since they tagged New Orleans for 77 first-half points on Dec. 29, 2017. Meanwhile, Matthews was 5-of-6 from 3-point range in the first half when he scored 17 of his 22 points.

“My teammates were following me and shots were going in tonight,” Mathews said. “But we were able to get stops and that’s what really fueled our offense.

“And we’ve got to continue to remember that when the offense isn’t going all the time like it did in the third quarter and they were able to cut the lead, we’ve still got to be a team that’s predicated on the defensive end first no matter what’s going on on the offensive end.”

As the Mavs figured, the Wizards (2-8) made a healthy run and sliced their deficit down to as low as six points on multiple occasions. After it was 99-93 Mavs, Dennis Smith Jr. hustled and snatched an offensive rebound and fed DeAndre Jordan for a high octane dunk.

Smith and Jordan hooked up again shortly thereafter when the former lobbed a pass high in the sky, which seemed way out of reach for Jordan. However, Jordan wowed the crowd when he contorted his body and snatched the ball out of thin air and somehow completed a reverse tip-in.

On the ensuing sequence, Smith galloped down the lane and found Harrison Barnes for a wrap-around layup and an and-one basket that gave the Mavs some breathing room and a 106-93 lead with just 4:25 left in the game.

“A very big sequence, but this is where you’ve got to trust your players,” Carlisle said. “We’re playing better basketball in flow situations off misses by far than we are off set plays.

“There’s a temptation often times in coaching is to grind and know where the ball’s going and things like that down the stretch. But Dennis has earned the trust. It doesn’t mean he doesn’t make mistakes, but he’s seeing things, and those two plays were real pivotal plays in the game, and it just kept them at a distance.”

While Smith was tying a neat little bow around his 19-point, seven-assist night, rookie Luka Doncic was just as splendid. Doncic collected a team-high 23 points and six rebounds, and just kept making critical basket after critical basket.

Wizards coach Scott Brooks said what Doncic is doing to NBA teams at age 19 is definitely not normal.

“He’s impressive,” Brooks said. “You don’t see that many payers coming in and averaging 20 (points) and five or six assists and just playing with the court vision.

“He’s a knockdown shooter, and that extra distance that he has to shoot from he’s already adapted well. Every game you look at him and you say, ‘OK, you sure this guy’s only 19.’ ”

Barnes also put on a really impressive show, finishing with 19 points, a game-high 13 rebounds and two steals. And Dorian Finney-Smith came off the bench to add 11 points, five rebounds and three blocks.

“I thought our start was great and I felt like it was more defensive for us,” said Jordan, who grabbed 12 rebounds while becoming the first Mavericks player to collect at least 10 boards in the season’s first 10 games. “The lead that we had early on in the game was from our defense.

“We didn’t have to take the ball out every time and we were able to push it in transition, and Dennis did a helluva job pushing the ball up. He set the tone for us, pace-wise, and we covered for each other all night tonight and everybody had each other’s back and we have to build off of that.”

NOTES: Luka Doncic has 198 points, 65 rebounds and 44 assists in his first 10 games. The only rookie in NBA history with similar numbers through his first 10 games is Oscar Robertson (255-102-92). “He seems like he’s been in the league for seven or eight years is how he’s playing,” Washington Wizards coach Scott Brooks said of Doncic. “He sees the floor as well as anybody at his position, he makes big shots. He just plays with a flair and an enthusiasm that you want, and a toughness and great effort that you want in your players to play with no matter how old he is. I don’t look at him as a young player. He’s a legitimate NBA player that’s going to be a superstar in this league.”. . .Coach Rick Carlisle said he guard Devin Harris (strained left hamstring) won’t play Wednesday against Utah. Carlisle said: “I don’t believe there’s any chance he’s going to play until the weekend.”