Williams beat Russian Maria Kirilenko 6-2, 3-6, 6-2 to set up an intriguing pre-US Open clash of former world No. 1s.

“I’m sure we’ll both go out and do the best each of us can,” Williams said. “It’s nothing personal. It’s my job and I want to get paid. I leave it on the court.”

Williams is playing her first tournament on US soil since the 2009 US Open. She missed nearly a year following right foot surgery. She also had blood clots in her lungs, and another surgery to remove a pool of blood under her skin.

She took a medical timeout during her match against Kirilenko to get her left ankle retaped after a blister formed, and the Russian took advantage by winning the second set and taking the first game of the third.

“I was a little sluggish out there,” Williams said. “I got upset and started playing well enough to win. I started out fine but after that injury timeout I was sluggish.”

Belarussian Azarenka was beaten 4-6, 7-5, 6-2 by New Zealand’s Marina Erakovic, a 121st-ranked qualifier who recorded her first win over a top-20 opponent, stunning the Wimbledon semifinalist.

“Coming in I knew I had to be the aggressor and try to dictate the pace,” Erakovic said. “I knew the court and I felt like I was hitting the ball well.”

Her quarterfinal opponent will be Slovakian Dominika Cibulkova.

Japan’s Ayumui Morita recovered to beat qualifier Urszula Radwanska of Poland 4-6, 7-5, 6-1 and will next face Marion Bartoli.

The 23-year-old Erakovic, born in Croatia, missed six months due to a hip injury in 2009 and returned via the ITF circuit, where she has won 12 singles titles.

“I went into a slump just before the injury and was beginning to question whether this tennis thing was for me,” Erakovic said. “The injury made me realize how much I love tennis and that’s when I committed myself. Coming back I feel like I can compete with the best.”
 
Top seed Peer beats Kudryavtseva at Citi Open

In College Park, Maryland, top seed Shahar Peer of Israel beat Russia’s Alla Kudryavtseva 6-1, 6-4 to advance to the quarterfinals of the inaugural Citi Open.

Peer, ranked 24th, made it to her first WTA Tour quarterfinal since early March. Her opponent in Friday’s quarterfinal will be eighth-seeded Alberta Brianti of Italy, who needed only 52 minutes to oust American Varvara Lepchenko 6-1, 6-2.

Third-seeded Tamira Paszek of Austria beat American qualifier Madison Brengle 6-3, 6-1 and will play Stephanie Dubois in the last eight. The Canadian advanced by dominating the tempo in the third set against Britain’s Heather Watson to win 3-6, 7-5, 6-1.

The other two matches in Friday’s quarterfinals are: second-seeded Nadia Petrova of Russia against fifth-seeded Serbian Bojana Jovanovski, and American Irina Falconi against Virginie Razzano of France.