DALLAS -- The Dallas Mavericks brought back one big man but lost another Tuesday night, and in the end, they couldn't rein in the reigning Finals MVP.
Powell went down to a non-contact, right Achilles tendon injury in the first quarter, and though he will have an MRI on Wednesday, the team is fearing a worst-case scenario.
"Guys like him define the culture we want here," Dallas coach Rick Carlisle said. "It doesn't get much tougher than this, if it ends up being what we fear it might."
Luka Doncic had 36 points, 10 rebounds and nine assists for Dallas. He scored 24 points in the second half to help rally the Mavericks after they trailed by double digits from late in the second quarter through most of the third.
Shamet helped the Clippers seize the game late in the fourth quarter. His 3 from the left wing to give Los Angeles a 100-98 lead with 2:48 to play. Montrezl Harrell added two free throws, then Shamet sank another 3 from straight-on to put the Clippers up by seven. He finished with 18 points.
"We just kind of found a way to win," Shamet said. "We'd loved to keep that lead the whole game, but that's not how it's going to be. It's a long season. We got to find different ways how to win like we did tonight."
Leonard added 11 in the fourth quarter, including his only 3 of the game with 1:15 left, which put the Clippers up 108-100.
But Dallas rallied, as Doncic hit a 3 and Maxi Kleber a dunk. After a Clippers turnover, Tim Hardaway Jr.'s potential tying 3 spun around and out. JaMychal Green missed two free throws for LA, but then Doncic missed two -- the second intentionally -- and Leonard sealed it with two free throws.
Powell went down when he started to drive toward the basket but his right leg gave out. He fell to the ground and immediately slapped the floor in pain. He was helped to the locker room putting no weight on his right leg.
Powell's teammate J.J. Barea -- who tore his right Achilles tendon last season -- was distraught as Powell was taken off the court.
Powell was averaging nearly 10 points a game in 39 games prior to the injury. With Porzingis out, Powell averaged 13 points over 10 games on 71% shooting.
With Powell out, Dallas got 16 valuable minutes from former Clipper Boban Marjanovic, who had 12 points and seven rebounds. His turnaround hook with 6:23 to play tied it at 90, capping a rally from a 14-point, second-half deficit.
Porzingis scored 10 points on 4-for-17 shooting in his return after missing 10 games with right knee soreness. He added nine rebounds, but after the game, he blamed himself for the Mavericks' loss.
"If I played just a little bit better, we would have won the game," Porzingis said. "This loss is on me. That's how I feel. I know it's my first game back but I have high expectations for myself and I'm disappointed I wasn't able to shoot the ball better."
LEONARD STEPS UP
With teammate Paul George out over the last six games, Leonard has averaged 36 and at least 30 in every game.
"We've been watching film together, seeing what mistakes we've been making," Leonard said. "So everybody's just giving the effort of their mind and body, wanting to compete, make winning plays and just be a better basketball team."
Clippers: George missed his sixth straight game with a left hamstring strain. ... G Patrick Beverley left in the second quarter with a groin injury and did not return. ... F Maurice Harkless returned after missing one game with a sore back.
Mavericks: The Clippers also ended a five-game Mavericks winning streak on Nov. 26.
Clippers: At Atlanta on Wednesday.
Mavericks: At Portland on Thursday.
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