ZAGREB, Croatia (AP) -Top-seeded Ivan Ljubicic advanced to the quarterfinals of the Zagreb Indoors on Thursday, overpowering Teimuraz Gabashvili of Russia with 19 aces in a 6-2, 6-7 (5), 6-3 victory.
Ljubicic, the 2006 champion and 2007 finalist, improved to 12-1 in Zagreb. The Croat is the last seeded player left, after No. 8 Janko Tipsarevic of Serbia lost 3-6, 6-4, 6-2 to Sergiy Stakhovsky of Ukraine.
Ljubicic will play fellow countryman Mario Ancic in the semifinals on Friday.
"That's the best that could have happened to the (Croatian) tournament," Ancic said of his upcoming duel with Ljubicic. "Let the better one win."
Ljubicic is 3-1 against Ljubicic.
Ancic defeated Robin Haase of the Netherlands 6-3, 3-6, 6-3 on the power of 13 aces. He appears determined to climb back into the world's top 10.
Ancic was ranked No. 9 when he dropped from the tour last year for six months because of mononucleosis. After missing January with a stomach ailment, he reached the Marseille final in his season debut this month.
Stakhovsky is the first lucky loser to reach an ATP semifinals since Ivan Navarro Pastor in Valencia, Spain, in April 2007. He made the main draw after Michael Llodra, last week's Rotterdam winner, withdrew.
Stakhovsky will play Simone Bolelli of Italy, who reached his first career semifinals by defeating Olivier Rochus of Belgium, 7-6 (5), 6-4.
