Defending champion Saina looked well on course to retain her title by thrashing her much inexperienced opponent Kristy Gilmour of Scotland in the women's singles second round to win 21-12, 21-7 in half an hour.
The World No.4 Indian forced her opponent to make errors and used exquisite drops at the net to make her way through to the last eight.
Earlier, World No.24 Gurusaidutt won 21-15, 21-16 in 35 minutes to extend his lead to 3-1 in career meetings over compatriot and friend Ajay Jayaram of Mumbai.
Gurusaidutt now has a tough task ahead of him as he faces third seed Du Pengyu of China in a last eight clash. However, the Indian can take heart from the fact that he beat the Chinese in Hong Kong two years ago.
--IANS (Posted on 17-10-2013)