The Chilean beat her South American rival Jenny Daza from Bolivia after a tie breaker, 15-8, 14-15, 11-5.

The result in San Jose means she now has a chance to win the group if she beats the world number three Samantha Salas from Mexico tomorrow.

Salas herself beat Ireland's Donna Ryder today, 15-1, 15-8.

The winner of the group, who will be confirmed tomorrow, will be seeded third in the play-off round, therefore avoiding the three-time champion and this year's favourite Paola Longoria.

The Mexican did not play today as she had a bye.

Argentina's Natalia Mendez has become the dominant player in Group G, by beating Colombian Cristina Amaya, 15-1, 15-8 today.

It is possible she could still miss out on the top spot, however, if she loses to Merynanyelly Delgado tomorrow.

Delgado, of Dominican Republic, beat the Canadian Jen Saunders today, 6-15, 15-12, 11-3.

In the men's event all of the matches today went as expected, although some were decided on tie-breakers.

Bolivia's Carlos Keller needed one to beat Chile's Johan Igor 15-8, 4-15, 11-6, while Jose Daniel Ugalde from Ecuador beat Guatemala's Christian Wer 13-15, 15-13, 11-5.

Ramon De Leon from the Dominican Republic beat Daeyong Kwon from South Korea, 10-15, 15-9, 11-7.