Naomi Osaka committed next month's tournament in San Jose, California, her first appearance since a first-round loss at the French Open on May 23.
The four-time Grand Slam winner accepted a wild-card entry into the Mubadala Silicon Valley Classic on Monday (Jul 18).
Osaka, 24, withdrew from Wimbledon due to a nagging injury to her left Achilles.
The San Jose tourney begins on Aug 1. Osaka joins a field that includes Wimbledon champ Elena Rybakina, World No 5 Ons Jabeur and American teenager Coco Gauff.