Favourite and third seed Harsh Mankad crashed out of the US $15,000 ITF Futures tournament in Delhi on Tuesday.
The Indian ace, ranked 348, was beaten by unfancied Uzbek player Denis Istomin, ranked 855, 7-6(5), 7-6(2).
Another Indian Karan Rastogi, a semi-finalist in the Mumbai leg, also fell by the wayside, losing to Uzbekistan's Murad Inoyatov 2-6, 6-4, 4-6.
Top seed David Sherwood of Britain overcame a spirited challenge from compatriot Michael Quvarov, winning 6-4, 6-4, while second seed Simon Greul, also of Britain, easily beat Divij Sharan 6-1, 6-1.
Fourth seed Norikazu Sugiyama of Japan also won easily. He beat qualifier Rahil Makharia 6-0, 6-1.
Lucky loser Shahab Nafez-Hassani of Ireland, who got into the main draw in place of Prakash Amritraj, who withdrew because of a shoulder strain, was routed by Ajay Ramaswami. He lost 0-6, 1-6.
Qualifier Arun Rajagopalan staged a fine rally after losing the first set to beat Russia's Sergei Krotiouk 4-6, 6-4, 6-4.
Vinod Sridhar was the third Indian to taste success. He defeated qualifier J Vishnu Vardhan 7-5, 7-6(8).
Konstantin Kravchuk (Russia) accounted for qualifier Sanam Singh 6-4, 6-3 while American Lester Cook survived a scare before getting past Iran's Ashkan Shokoofi. Cook won 7-6(8), 6-3.
