The former world number one, and twice a winner in the California desert, suffered a stunning defeat on Wednesday to Japanese No. 1 Naomi Osaka, losing in straight sets 6-4 6-4.
Sharapova was one of the tournament's major attractions after missing the last two.
"Maria has been one of the most hardworking and professional players I have ever worked with. Her strength and fighting spirit will continue to be a force to reckon with and I have the deepest respect for her as a player and person," said Groeneveld of the Netherlands.
For Sharapova the loss to the 20-year-old Osaka was another painful reminder that it's back to the drawing board for the Russian as she makes her way back from a 15-month drugs ban.
It was her second first round loss in a row after she withdrew from the Dubai tournament with a forearm injury.
In her only grand slam appearance this year, Sharapova reached the third round of the Australian Open before losing to Angelique Kerber.
- AFP