SOFIA, Bulgaria - They're the No.2 and No.3-ranked Russians in the world, together they're one of the best doubles teams in the world, and right now they can be found in the part of the world where eight of the best players in the world are battling it out for season-ending WTA glory - in beautiful Sofia, Bulgaria.
Trailing only Maria Sharapova, Nadia Petrova and Maria Kirilenko are the two best exports from Russia, and - fresh off the doubles title at last week's WTA Championships in Istanbul - they have travelled to Sofia to finish their singles seasons off at the Qatar Airways Tournament Of Champions Sofia.
Both of them played their first round robin matches of the week on Wednesday and both won in straight sets, beginning with the No.2-seeded Petrova, who beat No.6-seeded Zheng Jie, 63 63. It was her ninth win in the pair's 10 career meetings - and the only loss in that bunch came by means of retirement, too.
But Wednesday's win was anything but dominant, Petrova said: "The score may look a little easy, but it didn't feel easy to me at all. I started well but I wasn't feeling great on my serve - I didn't really feel in control of my game, and she broke my serve three times in the first set alone, which was disappointing.
"But I'm happy with my returning, and I'm hoping to serve better tomorrow."
In the next match on center court, No.3 seed Kirilenko cruised through the first set then bounced back from a 2-0 hole in the second set - saving two points for a 3-0 hole, too - to dispatch No.8 seed Tsvetana Pironkova, 61 64.
"I had never played against Tsvetana before. I saw a couple of games when she played yesterday, but it's always different just seeing the player and actually playing them," Kirilenko said after the match. "I decided to just see how it went the first couple of games, and then figure out what to do from there.
"I did everything right in the first set, I think. Everything was tighter in the second set, but that's normal, and I'm happy I could finish it in straight sets."
Petrova and Kirilenko are 1-0 in the Group Sredets round robin group now; Pironkova is 1-1, while Zheng is 0-2, having lost to Pironkova on Tuesday.
Not only have the two Russians been tearing up the doubles court together all year, they have both worked their way into the Top 15 in singles, even within striking distance of the Top 10. Petrova's season highlight came just a few weeks ago in Tokyo, where she won her 12th and biggest WTA title; Kirilenko had a slew of sizzling results during the summer season, reaching the quarterfinals of Wimbledon, the semifinals of the Olympics and the final of New Haven (after which she set a new career-high ranking of No.12).
Now Kirilenko and Petrova will play against each other in the only Group Sredets match on Thursday, with the head-to-head series tied, 4-4. They have only played once in 2012, with Kirilenko winning a bizarre one at Indian Wells, originally leading 61 51 but eventually closing it out, 61 57 62.
"I thought my game was awesome until 61 51, but then Nadia started playing very well," Kirilenko said after that match. "I wasn't making any mistakes - she was playing very aggressively and running well too. But I made sure to stay focused and not get upset, and just start fighting again in the third set."
"We've spent so much time playing and practicing this year that we know each other's weaknesses and strengths very well," Petrova said. "Tomorrow it'll be about who goes on the court and feels better and plays better on the day."