NEW YORK (AFP) - Samantha Stosur dropped an epic second-set tiebreaker but recovered to beat Maria Kirilenko 6-2, 6-7 (15/17), 6-3 to reach the US Open finals. Russias Kirilenko prevailed in what the WTA said was the longest womens singles tiebreaker at a Grand Slam tournament to knot the fourth-round match at a set apiece. Stosur moved will face second-seeded Russian Vera Zvonareva in quarterfinal. Zvonareva advanced with a 6-2, 6-3 victory over Sabine Lisicki, the big-serving German who had hoped to improve on her run to the Wimbledon semi-finals. Stosur has won the last seven of her meetings with Zvonareva, but said shed take nothing for granted. Stosur had already entered the record books this week when she toiled for three hours and 16 minutes to get past Nadia Petrova 7-6 (7/5), 6-7 (5/7), 7-5 in the third round. Stosur said she didnt expect the long hours shed been putting in to affect her against Zvonareva. Stosur, who had dominated in the opening set, said that once the tiebreaker was behind her she didnt find it too difficult to stay mentally strong. Italys Flavia Pennetta also stayed tough in the face of adversity as she carved out a 6-4, 7-6 (8/6) victory over a fighting Peng Shuai to set up a quarter-final meeting with German Angelique Kerber a 6-4, 6-3 winner over Monica Niculescu in a battle of unseeded players. Pennetta, the 26th seed, who shocked third-seeded Sharapova in the third round, had to fight to the finish against Peng, who saved one match point and gave herself four set points in the tiebreaker before Pennetta was able to reach the quarter-finals for the third time in four years.