Ace Indian shuttler Saina Nehwal entered the women's singles semifinals with a comfortable straight-game win, but compatriot P V Sindhu failed to cross the quarterfinal hurdle in the Star Australian Super Series in Sydney today.While Sindhu, seeded eighth, lost 17-21 17-21 against Carolina Marin of Spain, sixth seeded Saina got the better of Eriko Hirose of Japan 21-18 21-9 in 47 minutes to set up a clash against world no. 2 Chinese shuttler Shixian Wang in the last four stage of the tournament.Saina enjoys a 4-3 record against two-time All England champion Wang but the last couple of times they met, the Chinese had won on both the occasions.Sindhu, world no. 10, fought her heart out for 47 minutes but could not overcome the challenge posed by the 11th ranked Spaniard.