LOS ANGELES — Luka Doncic and the Dallas Mavericks dominated Boston 122-84 on Friday to fend off elimination in the NBA Finals, denying the Celtics a sweep in the best-of-seven championship series.

Doncic scored 25 of his 29 points in the first half, and Kyrie Irving added 21 for the Mavs, who snapped the Celtics' 10-game playoff winning streak but still have a mountain to climb as they try to become the first team to rally from a 3-0 deficit to win an NBA playoff series.

Now down 3-1, Dallas will try to stop the Celtics from celebrating an 18th title when they travel to Boston for Game 5 on Monday.

"Like I said at the beginning of the series, it's first to four," Doncic said. "We're going to believe until the end.

"I have big belief in this team that we can do it, so we've just got to keep believing."

Doncic, roundly criticized after Game 3 when he fouled out with more than four minutes left and could only watch as the Mavs' comeback bid fell short, was dialed in on the defensive end as Dallas held the Celtics to 36.2 percent shooting.

Boston star Jayson Tatum scored 15 points, and Jaylen Brown had just 10 as the Mavs posted the third-largest margin of victory in NBA Finals history.

"Thought they played with a ton of energy and physicality," Celtics coach Joe Mazzulla said of the Mavericks. "And they are a great team; that's the reason why they are here when they play like that."

Tim Hardaway Jr. added 15 points off the bench for Dallas, and 20-year-old rookie Dereck Lively added 11 — including his first career three-pointer — as the Mavs topped 100 points for the first time in the series.

Dallas handed Boston their first road defeat of these playoffs and ended their bid for the 10th 4-0 sweep in Finals history.

With Doncic and Irving leading the way, Dallas built a 34-21 first-quarter lead — the Mavs' highest-scoring quarter of the series.

There was no let-up in the second, with the Mavs dominating every facet of the game on the way to a 61-35 halftime lead.

Lively electrified the crowd at American Airlines Center with his three-pointer, followed by an alley-oop dunk on the next possession in the first period.

"I think our energy was way higher," Doncic said. "Everybody was locked in (on the) defensive end."

The Celtics, harried at every turn, made 14 of their 41 three-point attempts. They were out-scored 60-26 in the paint and out-rebounded 52-31 — Dallas' dominance on the boards leading to a 16-2 edge in second-chance points.

"They did a great job flying around, making indecision on whether to shoot it or drive and their multiple efforts," Mazzulla said. "And I thought their five men did a great job protecting the paint. Whenever we went in for a layup, they had multiple guys contesting."

Hell of a player

Doncic said it was the prospect of elimination more than criticism of defense that had him stepping up the intensity, forgoing his usual complaints to officials, and letting his game speak for him.

Stripped by Jrue Holiday on a drive to the basket, Doncic dived for the loose ball and swatted it to Irving, who played it back to him for a layup.

Fouled on the play, Doncic made the free throw to put Dallas up 43-25 midway through the second quarter.

Mavs coach Jason Kidd — and Mazzulla — said Doncic was just his normal MVP-candidate self.

"There was not a different Luka out there," Kidd said. "He's great, he's been great, he's one of the best players in the world; as much as we want to criticize him, he's a hell of a player."

The Mavs were up 92-57 when Doncic and Irving checked out of the game to a standing ovation with 1:29 left in the third quarter, with Irving offering Doncic a congratulatory embrace on the bench.

Mazzulla had already pulled his starters by then, their attention already turning to Game 5 and their next chance to break out of a tie with the Los Angeles Lakers for most NBA titles.