Playing before the home crowd at the BTA Complex courts, eighth seed Rupesh sprang the upset of the day showing top seed Daniel King-Turner of New Zealand the exit.
It took Rupesh 86 minutes to despatch the New Zealand Davis Cupper 6-4 6-2.
In-form Yuki, seeded fifth, stunned second seed Alexander Satschko of Germany 7-5 3-6 6-1 in 143 minutes.
Results (semifinals): (Indians if not specified): Singles: Rupesh Roy bt Daniel King-Turner (NZ) 6-4 6-2; Yuki Bhambri bt Alexander Satschko (Ger) 7-5 3-6 6-1 Doubles: Rohan Gajjar/ Purav Raja bt I-Ta Chen/ Cheng-Peng Hsieh (Tpe) 6-2 6-4.
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