Stan Wawrinka will try to follow up his US Open championship with another title in St Petersburg after beating Roberto Bautista Agut 7-6(8) 6-2 in their semi-final.
Unbeaten in 10 matches, the Swiss star must beat fifth-seeded Alexander Zverev to win the title after the German teenager disposed of Tomas Berdych in the first semi-final on Saturday.
Seeded first in St Petersburg, Wawrinka had to go through a tough first set against Bautista Agut.
The Spaniard had two set points in the tiebreaker and saved one of his opponent's before Wawrinka converted his second set point.
Bautista Agut couldn't respond in the second set as he won just seven points on Wawrinka's serve.
"For me to make the final, it's really good, really positive," said Wawrinka, who called Zverev "the future of tennis, for sure".
The German surprised third-seeded Berdych 6-4 6-4 and will chase his first career ATP title on Sunday in his family's original home country of Russia.
Zverev bombarded Berdych with fast, accurate serves while the Czech veteran struggled, landing just 44 percent of first serves in the second set and leading 30-20 on unforced errors overall.
Berdych had three break points when Zverev served for the match, but the German kept calm to fight back and close out the win.
At the Moselle Open in Metz, France, top-seeded Dominic Thiem will face Lucas Pouille in the final after rallying past local favourite Gilles Simon 4-6 7-5 6-3.
The 10th-ranked Austrian player, who remains on course to qualify for the season-ending ATP Finals for the first time, hit 10 aces and won 76 per cent of his first-serve points to prevail on Saturday.
The fourth-seeded Simon was up a break at 5-4 in the second set but could not seize his chance to serve out the match.
Frenchman Pouille defeated Belgium's David Goffin 7-6 6-1.
