The unseeded Indo-American pair fought hard before losing 7-5 4-6 5-10 in one hour and 56 minutes to Chinese Taipei combination of Hao-Ching Chan and Yung-Jan Chan in the USD 740,000 hard court event.
It was a roller-coaster contest for Sania and Bethanie as they came from no-where to win the first set as they were trailing 2-4 at one stage.
They though failed to carry forward the momentum, allowed the Taipei pair to draw parity before and then lost the match tie-breaker.
It was last tournament for Sania before the Olympics as she is to report to the team captain S P Misra in London July 23.