Ace Indian shuttler Saina Nehwal entered the semifinals of Japan Open Super Series badminton tournament in Tokyo after dispatching Singapore's Juan Gu in straight games in just half an hour, on Friday.The fourth-seeded Indian defeated Juan 21-17 21-13 to make the last-four stage, where she will take on Germany's Juliane Schenk.Saina was facing Juan after almost three years and the Indian dominated her world number 23 rival just the way she did in 2008.The 21-year-old Hyderabadi has a good chance of reaching the finals as well, as she has a good one-on-one record against Schenk.The two have faced each other seven times so far with Saina emerging winner on five occasions. They last played against each other in the 2010 Hong Kong Open with Saina emerging the winner.