BOSTON – Luka Doncic is not normally a man of many words.

He was a man of even fewer following Dallas’ 107-89 loss to the Boston Celtics in Game 1 of the NBA Finals.

“We didn't do our job well,” Doncic said. “So we've got to focus on the second one.”

Making his Finals debut, Doncic had a so-so game by his standards: 30 points and 10 rebounds, becoming just the first player since Tim Duncan in 1999 to record a 30-point double-double in his first Finals game.

He was 12-for-26 from the field, including 4-for-12 on 3-pointers, and he wasn’t the offensive force that propelled the Mavericks to the Finals.

He had just one assist which isn't sufficient. For a player who averaged a career-high 9.8 assists during the regular season and 8.4 through the first three rounds of the 2024 playoffs, the one assist was troubling. It was his lowest assist total for a single game since leaving a regular-season game against Phoenix with an early injury last season and finishing with no assists. In a game in which he played at least 20 minutes, it was his lowest single-game assist total since May 7, 2021.

“Give the Celtics credit," Dallas coach Jason Kidd said. "They did a great job defending, making it tough on us. We had some good looks that didn't go down. We've got to move the ball. The ball just stuck too much. And we'll be better in Game 2.”

Assists are dependent on teammates making shots, and the Mavericks didn’t do that. They shot 41.7% from the field and 25.9% on 3-pointers.

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“I think we really got good shots.” Doncic said. “We just didn't make them.”

It was a team effort by Boston, but Celtics guard-forward Jaylen Brown had a tremendous defensive game, which included guarding Doncic. Brown had 22 points, six rebounds, three steals and three blocks.

“What you saw tonight is kind of the challenge he took for himself coming into the year,” Celtics coach Joe Mazzulla said. “Not wanting to be defined by one thing. Wanting to make plays. Wanted to be a well-rounded player and get better and better. So his spacing, his ball movement, his defense on ball and off ball.”

Down 58-29 late in the second quarter and trailing 63-42 at halftime, the Mavs made a run in the third quarter. Doncic had 10 points, six rebounds and two steals in the third quarter, and Dallas cut Boston’s lead to 72-64 on Doncic’s 3-pointer with 4:28 left in the third.

“In those moments, we were playing our basketball,” Doncic said. “We were getting stops. We didn't allow them to offensive rebound. We were having fun out there those couple moments, and that's what we've got to do more."

Dallas had two chances to make it closer but committed two turnovers, and Boston used a 14-0 run to push the lead to 86-64.

Follow NBA reporter Jeff Zillgitt on social media @JeffZillgitt

This article originally appeared on USA TODAY: Luka Doncic nearly speechless after NBA Finals debut