Hingis, who received a first-round bye, used a variety of ground-strokes and effective forehand returns to deny Rubin, ranked No 24, any chance of making an impact in what was Hingis' first match since losing to Venus Williams in final at Zurich three weeks ago. "It was a good win," she said. "I hadn't played for a couple of weeks and was pretty focused."
Also advancing to the last eight was the fifth seed, Julie Halard-Decugis of France, who defeated Venezuela's Maria Vento 6-1, 6-4, and Lisa Raymond, of the United States, who beat Henrietta Nagyova of Slovakia, 2-6, 6- 3, 6-3.
Another American, Jennifer Capriati, beat the 16-year-old Kim Clijsters of Belgium, 7-5, 6-3.
The former men's world No 1, Marcelo Rios, will be absent from the ATP tour for four months after undergoing successful surgery on his pelvis.
The Chilean left-hander, currently ranked No 9 in the world, will miss the ATP event this month, the Australian Open in January, and will be doubtful for Chile's Davis Cup tie against Canada in February.