Unseeded Indian Davis Cupper Somdev Devvarman beat third seed and world No 94 Jesse Levine of the United States 7-6(5), 6-2 to enter the semi-finals of the US $75,000 ATP Challenger in Nashville, US.
He meets second seed Bobby Reynolds for a place in the final.
Somdev had earlier beaten Reynolds, world number 86, in the pre-quarter-final round of Lexington Challenger.
Meanwhile, the Indian pair of Ashutosh Singh and Harsh Mankad stunned the second seeded pair of Australia's Ashley Fisher and Jim Thomas of the United States 6-3, 6-4 to storm into the semi-finals of the doubles competition.
The Indians, who entered the main draw as qualifiers, are up against the American wild card pair of Scott Oudsema and Tim Smyczek.