World number one Caroline Wozniacki launched her defence of her Pan Pacific title with a win over three sets as US Open champion Samantha Stosur crashed out of the event on Tuesday.
"I had a very tough match in the US Open (against Stosur). Especially in the second set, I had to play the longest tie-break. I knew she is going to be a little bit different," said Kirilenko.
"Every time you win a Grand Slam, it's tough to play next tournament and I had a feeling that I have a chance today. I just took this chance."
Kirilenko, ranked 28th against Stosur's seventh, moved up a service break in the second set, but failed to keep the lead hitting a double fault on a break point to tie at 4-4 before losing the set.
The Russian again lost a service break in the final set to be tied at 4-4, but broke back in the following game to lead 5-4 and made no mistake as the Australian's backhand shot landed in the net on her second match point.
"I think I was playing really good today, especially in the first set. I was moving fast today from the beginning of the match to the end. I'm just happy with the way I played," said Kirilenko.
Stosur said admitted she had struggled for consistency.
"I think the difference was she stayed mentally very strong from the first point to the last point, while I was kind of up and down," she said.
Wimbledon champion Petra Kvitova of the Czech Republic safely qualified for the next round beating Mandy Minella of Luxembourg 6-2, 6-3 to stay on course for a potential quarter-final match against Maria Sharapova.
Earlier, third seed Victoria Azarenka of Belarus eased aside Irina-Camelia Begu of Romania 6-1, 6-3 to reach the third round, while fourth seed Vera Zvonareva of Russia outplayed Tsvetana Pironkova of Bulgaria 7-5, 6-0.
Ninth seed Agnieszka Radwanska of Poland defeated Angelique Kerber of Germany 3-6, 6-3, 6-3, and Julia Goerges of Germany outclassed Greta Arn of Hungary 6-2, 6-1 set up a match against two-time champion Maria Sharapova.
Source: AFP Global Edition