Washington, who scored 14 points, came from Charlotte, and both newcomers had alley-oop dunks on assists from Doncic within minutes of entering the game in the first quarter.
Doncic, who sat the fourth quarter, had nine assists and eight rebounds as Dallas improved to 4-0 with Doncic and Irving in the lineup since Irving’s return from a sprained thumb.
The Mavs tied their highest-scoring quarter of the season with a 47-30 lead after the first, led by 18 points from Doncic as the Thunder allowed their most points in a quarter in 2023-24.
Oklahoma City, which came in a half-game behind Minnesota for the best record in the Western Conference, got as close as four midway through the second quarter after trailing by 22 late in the first.
The Mavericks were back in control in the second half when Gafford rebounded a missed 3-pointer by Irving and got fouled on the put-back. His free throw put Dallas up 110-89 in the final seconds of the third quarter.
Irving had eight assists, including the 4,000th of his career in the second quarter, as the Mavs finished one point off their season high.
Reporting by The Associated Press.
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