BEIJING, China - Maria Kirilenko and Nadia Petrova and Raquel Kops-Jones and Abigail Spears, the two teams in contention for the fourth and final spot left at the TEB BNP Paribas WTA Championships - Istanbul 2012, were victorious on Wednesday to secure quarterfinal spots at the China Open.

Kirilenko and Petrova, currently in fourth place in the standings, recorded a 63 36 106 triumph over Jelena Jankovic and Andrea Petkovic. In their 30th match win of the season, the No.2 seeds fought off 11 of 13 break points and actually lost two more points than they won.

Kops-Jones and Spears, barely behind the Russians in fifth place in the race, reeled off 12 straight points from 4-3 down in the second set tie-break en route to a 46 76(4) 106 defeat of Daniela Hantuchova and Peng Shuai. It was the eighth-seeded Americans' 10th straight win and 80th of their partnership.

Also coming through in a match tie-break were No.5 seeds Nuria Llagostera Vives and Sania Mirza, 46 63 119, over Timea Bacsinszky and María José Martínez Sánchez. Llagostera Vives had been 0-3 (0-1 in WTA matches) against her frequent partner Martínez Sánchez, with whom she has netted nine WTA titles. Llagostera Vives won here in 2005 alongside Maria Vento-Kabchi.

The day's lone upset saw Julia Goerges and Barbora Zahlavova Strycova take out two-time Grand Slam champions and No.4 seeds Vania King and Yaroslava Shvedova, 76(6) 62. Interestingly enough, Goerges and Zahlavova Strycova ousted two-time major titlists Lisa Raymond and Samantha Stosur in their opener.

Also securing berths in Thursday's quarters were No.6 seeds Katarina Srebotnik and Zheng Jie and No.7 seeds Anna-Lena Groenefeld and Kveta Peschke. Peschke and Srebotnik captured Beijing last year with each other.