New Delhi, Oct 14 (UNI) Wednesday proved a tough day for the top seeds, with several falling to lower-ranked opponents in the third round of singles at the 31st Fenesta Open National Tennis Championship at the DLTA Complex here Second-seeded Lakshya Chukka was among those as he was defeated by Haryana’s Harsh Marwaha 6-2, 6-4 in the boys U-16 event.