St Petersburg - Second-seeded Janko Tipsarevic will take on seventh-seeded Alex Bogomolov Jr in the semifinals of the St Petersburg Open after both men maintained their good form in Russia on Friday.
The other semi-final will feature fourth-seeded Marin Cilic against the 2004 winner Mikhail Youzhny, seeded fifth.
In Friday's quarterfinals, Tipsarevic, who won his second title at the Kremlin Cup on Sunday, rallied to beat Potito Starace 6-7 (7/6), 6-2, 6-1, while Bogomolov, who reached the quarter-finals in Moscow, beat Serbian qualifier Dusan Lajovic 6-2, 6-1.
"I haven't played Tipsarevic for a long time," said Bogomolov, who beat him in three sets in Tokyo in 2004. "But I do not expect any surprises from him tomorrow."
Later, Cilic advanced to his third semi-final this season after rallying to beat Andreas Seppi 4-6, 7-6 (10/8), 6-4, and Youzhny made it into his fourth semi-final with a 6-2, 6-3 victory over Adrian Mannarino.
"He (Youzhny) is a tough player for me to play, but this year we are 1-1 and had tight matches," said Cilic, who is 5-1 down against the Russian. "I think, it's important for me to keep pushing myself and try to play tomorrow really good."
Youzhny won four consecutive games in the first set and was leading 5-2 in the second. Mannarino saved two match points on his serve before Youzhny served the match out with a winner on his first match point.
Seppi, who won his first title in Eastbourne, England, in June, broke twice in the first set, but Cilic saved a match point on a second-set tiebreaker with an ace and converted a set point to stay in the match. The 22nd-ranked Croat broke decisively in the ninth game of the third set and fired his 13th ace of the match to finish it in the next game.
"I think, Seppi has played one of the best matches I've ever played against him," Cilic said. "He was serving really high percentage of the first serve and I wasn't getting any chances to break him. Toward the end of the match I was getting better and my serve helped me in the end."
Cilic advanced to the final three times from nine quarter-finals he has reached this season, but is yet to win.
Starace won four straight points in the tiebreaker to take the first set but the 13th-ranked Tipsarevic reeled off four consecutive games in the second set and five more in the third to secure his eighth semi-final appearance this season.
"The problem (in the first set) was that I didn't use my chances. I had two set points in the tiebreaker," Tipsarevic said. "It's same like in football - if you don't score the other guy is going to score. But then in the second set, when I made the break at 3-2 to 4-2, everything changed, I started feeling more relaxed and the match finished pretty fast."
Tipsarevic landed 12 aces in the match and is 7-2 in quarter-finals this season.
Bogomolov, still looking for his first ATP title, broke Lajovic twice in the first set and three times in the second for his second consecutive victory over the 228th-ranked Serb.
The Russian-born American also beat Lajovic in the first round at the Kremlin Cup in Moscow last week. Lajovic was playing in his first ATP quarter-final.
It is the second time this year that Bogomolov has reached a semi-final. He also made the final four in Los Angeles in June.