Fourth seed Thomaz Bellucci ousted World No.74 Jerzy Janowicz of Poland in the quarterfinal of the Kremlin Cup here.
The Brazilian No.1 converted his only break point in the first set to take it and won the second on a tie break returning from 5-3 down to secure a 6-4, 7-6(3) win Friday.
Bellucci advances to the semifinal on his first appearance here and will face Ivo Karlovic, ranked 130th, who dispatched French qualifier Edouard Roger-Vasselin earlier. This will be their third clash, with the Croatian veteran winning both previous in 2008.
The second semifinal will see second seed Andreas Seppi play Malek Jaziri of Tunisia. Second-seeded Italian Seppi took advantage of error-strewn play from eighth seed Tatsuma Ito to reach the semifinals.
Japan's Ito twice gave Seppi a break with a pair of double faults, once in the first set and once in the second, and made regular errors on key points as Seppi won 6-2, 6-1.
"It was a very good match from my side, no mistakes, and I served well when I needed to," Seppi said, conceding that Ito's mistakes had aided his progress.
"For sure, it helps you a lot if you don't have to play the big points."
Seppi now faces the unseeded 112th-ranked Tunisian Malek Jaziri, who has beaten 2010 champion Viktor Troicki, Czech player Lukas Rosol and Rajeev Ram of the United States on his way to the semifinal.
Last year, Seppi was the eighth seed when he reached the quarterfinals in his only previous appearance in Moscow before losing to German qualifier Michael Berrer 4-6, 6-3, 6-2.