Smith finished with 18 points, 14 rebounds and eight assists for Atlanta, which triumphed for the third time in four games.
Marreese Speights provided 23 points and eight rebounds for the Cavaliers, who fell for the ninth straight outing.
Cleveland again played without all-star guard Kyrie Irving, who sat out after netting 31 points in his return from an eight-game shoulder injury absence Sunday against New Orleans.
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