Nedunchezhiyan breezed through the first set and was leading 3-1 in the second when Roy broke back to force a tie-break and clinch it.

Nedunchezhiyan, who trained at the Krishnan Tennis Centre in Chennai, raced to a 4-0 lead in the decider before cramping. Though in pain, Nedunchezhiyan decided to carry on, allowing Roy to take the set to the tie-breaker. He, however, could not carry on for long as he went down clutching his leg and had to be carried off the court.

Roy next plays last week's winner and third seed Kim Young-jun who dispatched Briton Sean Thornley 6-1, 6-3.

In the other singles matches, Vivek Shokeen pulled off an upset, beating fourth-- seeded Kento Takeuchi 6-3, 6-4. Shokeen next plays Australian of Indian origin K. Balakrishnan who advanced as Hsien-yin Peng of Chinese Taipei retired trailing 6-2, 2-0.

Top seed Vishnu Vardhan overcame wildcard N. Prashanth 7-5, 6-3 in a keenly contested match. Vardhan next plays Vijayant Malik, who dispatched Yannick Nelord 6-3, 6-3.