Tokyo, Japan (My Sportsbook) - Elena Dementieva caught the upset bug on Tuesday, falling to unseeded Kateryna Bondarenko in second-round play at the $2 million Pan Pacific Open.

One day after the tournament's top two seeds -- Dinara Safina and Venus Williams -- were given an early exit, the No. 3 seeded Dementieva of Russia was handed a 6-2, 6-7 (3-7), 6-1 defeat at the hands of the Ukrainian Bondarenko on the hardcourts at Ariake Colosseum.

Two more Russians were upset Tuesday, as sixth-seeded Vera Zvonareva was bested by compatriot Alisa Kleybanova, 3-6, 6-4, 6-2, and No. 13 seed Nadia Petrova fell in straight sets to Magdalena Rybarikova of Slovakia, 6-2, 6-2.

There was some semblance of normalcy in the second round. No. 8 seed Victoria Azarenka of Belarus pounded China's Zheng Jie, 6-1, 6-1; 14th-seeded Marion Bartoli of France took a 6-4, 6-2 win over compatriot Aravane Rezai; and Li Na, the 15th seed from China, took a 7-5, 6-0 decision over Vera Dushevina of Russia.

In unseeded second-round action Tuesday: Russian Elena Vesnina defeated Roberta Vinci of Italy, 6-1, 7-6 (8-6); Iveta Benesova of Argentina outlasted Czech Gisela Dulko, 6-3, 3-6, 6-4; and Czech Lucie Safarova trumped China's Peng Shuai, 6-3, 4-6, 6-4.

Four more matches are still scheduled for Tuesday.

This week's winner will take home $350,000.