The Indian ace overcame an indifferent start to beat Vanni 1-6, 6-4, 6-4 in the semi-finals of the $50,000 hard court tournament after two hours and 14 minutes.
He will have a shot at two titles on Sunday as he has also reached the doubles final with compatriot Sanam Singh.
The 143rd-ranked Somdev turned it around amazingly as he broke his opponent, ranked 170th, twice after losing his own serve thrice.
He will fight it out with Japan's Yoshihito Nishioka for his second title of the season.
He won the $100,000 Delhi Open in February.
The doubles final will be an all-Indian affair as Sanam and Somdev face Yuki Bhambri and Divij Sharan, who edged past the Taipei pair of Ti Chen and Hsien-Yin Peng 7-6 (2), 7-6 (2) in the semi-finals.
Image: Somedev Devvarman
Photograph: Saleh Salem/Reuters
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