Down to the final eight in the women’s singles competition at the 2013 China Open and the usual suspects—world number one Serena Williams, Agnieszka Radwanska and Li Na are still in contention for the crown in the tournament held in Beijing, China.

The remaining top seeds have valid reasons to be worried. After all, other ranked players have already fallen by the wayside. This includes 2nd seed Victoria Azararenka, who is also ranked #2 in the world, loss to Andrea Petkovic, 4-6, 6-2, 4-6, in the opening round.

READ ALSO: 2013 China Open: Women’s Final Preview – Jelena Jankovic vs. Serena Williams Live Streaming

Williams did avert the upset in her Round of 16 match with Russian Maria Kirilenko. The world number one had to go through a humdinger of a battle but still prevailed in straight sets, 7-5, 7-5.

That close victory set-up a quarterfinals date with Caroline Wozniacki, who took Sloane Stephens to school, 6-3, 6-1, in the previous round.

As expected, Williams holds the edge in her head-to-head history against Denmark's number one player.

In six matches, the 32-year-old American has won five outings vs. Wozniacki, including the last two. The most recent one was in the 2012 London Olympics where Williams easily prevailed, 6-0, 6-3.

The lone win (6-4, 6-4) by Wozniacki came in the quarterfinals of a Miami tournament also in 2012.

Both Williams and Wozniacki have had successful runs in the China Open. Williams went all the way to the title in 2004 and Wozniacki won in 2010.

Another previous China Open champion is Jelena Jankovic, who won in 2008. She battles Lucie Safarova, who won in a three-set classic, 6-4, 6-7 (4), 7-6 (1) in the Round of 16. Jankovic’s own R16 match was a complete contrast as she won with a double bagel over Carla Suarez-Navarro.

Meanwhile, Petra Kvitova battles Li Na and Agniezka Radwanska faces Angelique Kerber in the other quarterfinals pairings.

2013 China Open - Quarterfinals Live Streaming and Schedule
LINK (Other links added once available)

Oct 4, 2013 (Friday) Matches (Australian Eastern Standard Time)

2:30 p.m. J. Jankovic vs. L. Safarova
5:00 p.m. P. Kvitova vs. N. Li
6:30 p.m. S. Williams vs. C. Wozniacki
9:00 p.m. A. Radwanska vs. A. Kerber