LONDON (AP) — BMX rider Arielle Martin underwent a third surgery after injuring her liver and lung in a devastating crash that knocked her out of the London Olympics.

Martin's family said Tuesday in a statement that doctors are hopeful Monday's latest surgery will help with fluid build up in her abdomen. A previous surgery removed about two liters of fluid.

The gold medal hopeful crashed after a mechanical problem during a final practice with the U.S. team on July 30 in Chula Vista, Calif. She was rushed to a hospital with a severe liver laceration and a collapsed right lung, injuries that initially were deemed life-threatening.

Martin has since been upgraded from intensive care to a trauma unit.

USA Cycling announced last week that 19-year-old Brooke Crain would take Martin's place on the Olympic roster. Crain traveled with the team to London last week.

The BMX competition begins Wednesday with seeding runs.