Ramkumar Ramanathan notched up a straight set win over Canada's Vasek Pospisil to reach his first ever ATP semi-finals but veteran Leander Paes bowed out after losing his doubles quarter-final at the Hall of Fame Open grasscourt tournament in Newport.
The 23-year-old from Chennai took one hour and 18 minutes to get across Pospisil 7-5, 6-2 in the quarter-finals on Thursday.
The 161-ranked Indian will meet American Tim Smyczek in the last four of the tournament.
Ramanathan, who had stunned world No. 8 Dominic Thiem at the Antalya Open last year, sent down five aces and converted the three break points that came his way.
Paes, who is playing his first match since creating the Davis Cup world record in February for most number of wins in doubles, and his American partner Jamie Cerretani suffered a 3-6 6-7 (3) loss to giant-killers Jeevan Nedunchezhiyan and Austin Crajicek in the doubles quarter-finals.
Jeevan and Austin, who had toppled top seeds Nicholas Monroe and John-Patrick Smith in the first round, will face fourth seeds Spain's Marcelo Arevalo and Mexico's Miguel Angel Reyes-Varela in the semi-finals.
In-form Divij Sharan and his partner Jackson Withrow, seeded second, defeated Australia's Matthew Ebden and Ukraine's Sergiy Stakhovsky 7-6 (4) 6-3 to set up a semi-final clash with New Zealand's Artem Sitak and Israel's Janathan Erlich.
Artem and Janathan saw off third seeds India's Purav Raja and British Ken Skupski 4-6 6-3 10-8 in a thrilling quarter-final contest.