Slovakia's Martin Klizan battled back from a set down to beat Stan Wawrinka on Saturday and reach the Saint Petersburg Open final.
Klizan, the 2012 champion here, won in 4-6, 6-3, 7-5 in two hours 16 minutes to chalk up his first win over the 33-year-old Wawrinka in their fourth head-to-head meeting.
"It was a very tough match," Klizan said. "Stan is one of the best players in the world and I'm really proud of myself after I could beat him finally.
"I'm going to do my best to win the title here. It's always a pleasure to play in the final."
The Swiss triple Grand Slam champion, who was a wildcard entry, broke Klizan in the first game of the match and went on to win the opening set in 36 minutes.
On his own serve, Wawrinka did not even allow Klizan to reach deuce until the sixth game of the second set. Then the Swiss seemed to suddenly lose his nerve, making a catalogue of unforced errors to allowing the Slovak to break to love. Klizan went on to take the set.
In the deciding set, Klizan broke in the third game. Wawrinka quickly broke but 29-year-old Slovak produced the deciding break in the 11th game to win the set and the match.
In Sunday's final, Klizan will face the winner of the semi-final between top-seeded Austrian Dominic Thiem and fifth-seeded Spaniard Roberto Bautista Agut.