In the second round qualifiers, third seeded Vishnu came back from a set down to register 6-7(5) 6-3 6-3 win in an hour and 51 minutes against Germain Gigounon of Belgium. Vishnu hammered 16 aces during the match.
He will now take on Martin Emmrich of Germany in the final round tomorrow.
Sixth seeded Sanam also made it to the final qualifying round after outplaying Georgia's Aleksandre Metreveli, grandson of former Russian tennis great Alexander Metreveli, 6-2 6-4 in an hour and five minutes.
The Indian will face another Georgian, fourth seeded Nikoloz Basilashvili for a place in the main draw.
Meanwhile, another Indian Davis Cupper, Yuki Bhambri has been drawn to play eighth seeded Karol Beck in the first round of the main draw that begins here tomorrow.
Divij Sharan and Yuki, the lone Indian pair in the doubles draw, will take on third seeded German duo of Andre Begemann and Martin Emmrich in the first round.
