Top seed Lindsay Davenport said she was not on top form despite easing into the Wismilak International quarter-finals. The American beat Rika Fujiwara of Japan 6-3 6-2 in Bali but had to save several break points in the first set.
"I did not play my best and know I have to get better," said Davenport, who will meet either Italy's Maria Elena Camerin or Russian Ekaterina Bychkova.
Also into the last eight are fourth seed Francesca Schiavone of Italy and seventh seed Na Li of China.