Chris Kaman contributed 12 points with seven rebounds and Sean Marion donated 11 and 14 as the Mavs grabbed control of the contest by outscoring the Wizards 35-19 in the third quarter.
Washington, meanwhile, fell for the 10th time in 11 games despite 22 points from Bradley Beal.
Emeka Okafor provided a double-double of 14 points and 11 boards in the loss.
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