DALLAS (AP) - 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.
Leonard also had the dunk of the night going right over Luka Doncic.
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.