By james art 
No Luka Doncic for the 16th straight game. Dereck Lively II in a giant walking shoe. The reigning Western Conference champion Mavericks are teetering on playoff territory.
In those and other glaring ways, much had changed in the 222 days since Dallas and Boston last met in the NBA Finals, but Saturday’s result at the American Airlines Center was somehow freshly familiar.
Boston 122, Dallas 107.
Little that happened this afternoon and evening evoked echoes of last June’s Finals, mostly because the injury-ravaged Mavericks are a shell of last season’s team. But two days after knocking off Oklahoma City, Dallas was hoping to somehow measure up to reigning champion Boston.
“We just have to look in the mirror and see how we can improve after that,” said Kyrie Irving, who led Dallas with 22 points on 11-for-23 shooting. “Because going against the best of the best, you have nothing but lessons to take from both games.”
Whatever the Mavericks (24-22) could take away from Saturday was tempered by what was taken from them. Again.
Already down to a healthy prototype center, Daniel Gafford, Dallas late in the third quarter saw backup center Maxi Kleber hobbled off the court and into the locker room with what the Mavericks later announced was a broken right leg.
Lively is out for at least a month and most likely several months and Dwight Powell (hip strain) is nowhere close to returning. Asked if his team had reached a critical mass at center, Mavericks coach Jason Kidd responded with an expression of glee and blunt assessment.
“This is difficult. I’ve never seen anything like it. And it’s not going to get any better,” Kidd said.
Boston (32-14) was outrebounded just 51-49, but 17 of the Celtics’ rebounds came on the offensive end.
It probably didn’t help Dallas’ cause that Boston entered with three losses in its last six games, most recently a 21-point loss at the Lakers.
Celtics center and former Maverick Kristaps Porzings, who on Saturday scored 18 points in his first AAC game since the Feb. 10, 2022, trade from Dallas to Washington, said Boston is trying to regain its killer instinct from last season.
“We were a lion last season,” he said. “Some games this year we looked like a house cat.”
On Saturday, they were Lions again, committing zero turnovers in the first half and five overall.
Kidd called it “just another game” beforehand, but the behavior of Mavericks Finals like Irving, PJ Washington and Gafford said otherwise in the opening minutes.
Dallas jumped out to a 16-6 advantage, but that turned out to be its largest lead of the game. The Celtics took control, outscoring Dallas 26-8 to start the second quarter and took a 59-49 halftime lead.
The Celtics doubled their lead to 96-76 in the fourth quarter, and then it was a matter of enduring Dallas’ desperation.
For Irving, it was his 15th loss in 16 games against Boston — including 1-7 as a Maverick — since leaving the Celtics in free agency after the 2019 playoffs.
It’s been seven months since these teams shared the court, on June 17 in Game 5 of the Finals. Green and white confetti floated from the TD Garden as the Mavericks walked off the court in defeat, 106-88.
Irving shot 5-of-16 tonight and 41.4% for the series, including 27.6% on 3-pointers. His streak averages of 19.8 points, 5.0 assists and 3.0 rebounds were well below his regular season averages of 25.6, 5.2 and 5.0. He then noted how the Celtics blitzed him on every drive.
“So that’s what the summer is about, continuing to work on those things that I saw this year,” he said. “Physicality, being able to adjust to it and be in a better position by next year.”
On Locked on Mavericks podcast on the eve of this season, he was more blunt about his Finals performance: “It’s not the best reflection of who I am.”
Individually, Irving’s numbers were better against the Celtics on Saturday, but for the Mavericks, the result was all too familiar.
They will see the Celtics again in Boston on Feb. 6, the day of the trade deadline. Maybe by then they’ll have Doncic back, or almost back.
Regardless, last June’s finals are becoming an increasingly distant memory and the chances of a return this June are getting slimmer with each injury.
Finals rematch: See photos from Saturday afternoon’s Mavericks-Celtics game
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