The Suns rallied from a slow start and early 12-point deficit to take a 50-44 lead at halftime and quickly extended their advantage. Dudley hit a 3-pointer and completed a three-point play in the first 90 seconds of the third quarter to give Phoenix a 58-44 lead.
Beasley added four straight points on a 7-foot jumper and a dunk to give Phoenix a 76-60 with 2:24 left in the period.
Sacramento whittled the lead to 81-75 on a layup by Thomas Robinson with 7:54 remaining. But Morris hit a 20-footer and a dunk, and Dudley scored 11 points in the game's final 3:07 as the Suns opened their biggest lead, 103-85, before settling for the 15-point win.
Featuring what, barring injury or other surprises, will be the season-opening starting lineup, the Suns got off to a sloppy start. In the game's first four minutes, Phoenix committed seven turnovers, missed three shots and fell behind 12-2.
But the Suns started to work themselves back into the game and took the lead for good on a 16-foot jump shot by Dudley with 46 seconds left in the first half.