Updated

Top seed Kirsten Flipkens advanced to the quarterfinals, while defending champion Sofia Arvidsson lost to last year's runner-up Marina Erakovic in second-round action at the $235,000 U.S. National Indoor Tennis Championships.

The Belgian Flipkens snuck past Ukrainian Lesia Tsurenko 7-5, 3-6, 6-3, while New Zealand's Erakovic avenged a defeat at the hands of the second-seeded Arvidsson in last year's Memphis final with a 6-1, 3-6, 6-3 victory Wednesday on the hardcourts at The Racquet Club of Memphis.

In addition to topping Erakovic in last year's finale, Arvidsson also titled here in 2006 and was the Memphis runner-up in 2010.

In other second-rounders involving seeds, No. 3 oft-injured German slugger Sabine Lisicki edged out Hungarian Melinda Czink 7-6 (7-0), 4-6, 6-2, No. 4 Heather Watson of Great Britain came back to defeat Czech Andrea Hlavackova 2-6, 6-0, 6-3 and No. 8 Kristina Mladenovic of France drove out American wild card Victoria Duval 6-1, 3-6, 6-3.

Meanwhile, Swiss Stefanie Voegele overcame French qualifier Claire Feuerstein 3-6, 7-6 (7-2), 6-1.

The quarterfinals will pit Flipkens against seventh-seeded Slovak Magdalena Rybarikova; Lisicki versus Mladenovic; Watson against Voegele; and American Jamie Hampton versus Erakovic. Rybarikova was the Memphis champ in 2011.