(CNN) -- Holder Kim Clijsters has continued her march towards a second successive U.S. Open title with a convincing straight sets victory over Serb Ana Ivanovic on Sunday.
The Belgian second seed took under an hour to thrash Ivanovic 6-2 6-1 and will now play Samantha Stosur in the last eight --- her 17th appearance in a grand slam quarterfinal.
Clijsters, who is seeking her third win at the tournament after successes in 2005 and 2009, told the official WTA Tour website: "I think you automatically do well in places where you have done well and you feel good."
The 27-year-old is aiming to become the first U.S.Open champion to retain her title since Venus Williams in 2001.
Australian Stosur advanced at the expense of Elena Dementieva, coming out on top in a record-breaking match.
The contest between the fifth seed and the Russian Dementieva ended later than any other women's tie in U.S. Open history, with Stosur eventually taking the match 6-3 2-6 7-6 thanks to a third-set tie-break.
Meanwhile, French Open champion Francesca Schiavone is also in the quarterfinals after a crushing victory over 20th-seeded Russian Anastasia Pavlyuchenkova.
The sixth-seeded Italian cruised to a 6-3 6-0 victory in just 68 minutes and will now face Venus Williams for a place in the semifinals.
"It was a very special win," Schiavone said. "I'm very lucky to play so well again in a tournament like this. I feel better with my touch."
Third seed Williams secured her place in the quarterfinals with a hard-fought 7-6 6-3 win over 16th-seed Shahar Peer.
The two-time champion needed a tie-break to clinch the opening set, before taking the second to advance to her 10th quarterfinal at Flushing Meadows.