The two-time Wimbledon champion committed 17 unforced errors in the first set and never got into the match, which was completed in 77 minutes.
The fast-starting Radwanska won the first five games of the match and then reeled off the opening four of the second set to stay in control throughout.
The Pole advances to face Ukrainian Elina Svitolina, who overcame Johanna Larsson 6-4 6-2 to reach the final.
Larsson enjoyed an improbable run in the tournament after reaching the main draw when other players withdrew, the Swede upsetting Italy's Roberta Vinci in the quarter-finals before coming up short against the 21-year-old Svitolina.
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The 10th-seeded Svitolina shocked Serena Williams on her way to a quarter-finals at the Rio Olympics and a victory in this warm-up event for next week's U.S. Open would be her second of the year after she triumphed in Malaysia in May.
(Writing by Jahmal Corner in Los Angeles; Editing by John O'Brien)
