Bangalore:Kerala's Ayyappan Krishnan shocked top seed T Dinesh of Andhra Pradesh but then bowed out in the quarter-finals of the Under-19 boys singles of the Union Bank All India Junior Ranking Badminton Tournament. Krishnan upset Dinesh, who was instrumental in Andhra winning both the senior and junior South Zone inter-state championships held in Pondicherry recently, 15-12, 15-8. But in the last eight, Krishnan lost to Karnataka's Utsav Prakash 11-15, 10-15. Joining Prakash in the semi-final were second seed Sagar Chopda of Maharashtra, third seed Rohan Castelino of Karnataka, who is national junior champion, and Amar V of Karnataka. Chopda came from behind to outlast Anshuman Hazarika of Assam 13-15, 15-6, 15-13, Castelino sidelined Mayank Behl of Railways 15-11, 15-8, while Amar defeated Shashank Sastry of Karnataka 15-13, 15-5. In the girls under-19 singles, teen sensation Saina Nehwal of Andhra Pradesh, fresh from her upset wins over top women players like B R Meenakshi and Trupti Murgunde, moved into the semi-finals with a 11-4, 11-2 victory over Neha Pandit of Maharashtra.