Webster hit seven shots from 3-point territory for the Wizards, who fired in 66.7 percent of their field goal tries en route to the one-sided victory.
Phoenix got 21 points off the bench from Michael Beasley but it wasn't enough to prevent a fourth straight loss.
Jared Dudley contributed 16 points for the Suns.
Ray Liotta sues skin care company over use of likeness
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