Russians claimed five of the eight spots in Friday's quarterfinals of the concluding edition of this event, which will fall victim to a WTA calendar shakeup for 2008.

The top seed and defending champion swept the first nine games in a 6-0, 6-3 win over French 13th seed Tatiana Golovin.

"It was not as easy as it looked," said the two-time grand slam winner. "About half of those first games went to deuce. I gave back two breaks in the second set and was lucky to get the win in straight sets."

Sharapova is dealing with a long-running shoulder problem that will not get worse and will slowly heal, doctors tell her.

Unseeded Maria Kirilenko followed the winning example, defeating ailing second seed Jelena Jankovic 6-2, 3-6, 7-5.

Jankovic, who qualified along with Justine Henin into the year- end WTA Championships field this week, said she was suffering from a cold during the 2hr 44min defeat.

The world number three Serb had a dozen break point chances against Kirilenko, with the Russian saving nine of them.

"Maria really played well, it was one of her best matches," said Jankovic. "I was struggling the whole time. I didn't do the right things and she took her opportunities.

"It's difficult when you're not feeling so well. I tried, but it was just not good enough.

"This was my first match after my holiday. I still need to get back to work on my physical training and be ready for more matches."

The pair of Russian winners were joined in the last eight by compatriots Anna Chakvetadze, Nadia Petrova and Elena Dementieva.

Number three Chakvetadze won her 11th straight match, beating Ai Sugiyama 6-4, 6-4 while fourth seed Petrova eliminated Slovenian Katarina Srebotnik 6-3, 7-6 (12/10).

Dementieva, the ninth seed, dealt fifth-seeded Wimbledon finalist Marion Bartoli a 6-4, 7-5 loss.

Bartoli said she is not overly concerned over her post-Wimbledon swoon which has left her 1-2 after two weeks on hardcourt almost a month after her surprise run at the All England club, where she lost to Venus Williams.

"My level was pretty good, but it was a hard match and I didn't play the right tactics. I had chances to close out the second set and get back into it, but I didn't take them."

Dementieva next plays Kirilenko, while Chakvetadze will face Wimbledon champion Williams. The 10th-seeded American advanced with ease, dismissing sixth-seeded Slovakian Daniela Hantuchova 6-0, 6-3.

India's Sania Mirza handed Russia its only setback of the day, beating eighth seed Dinara Safina 6-1, 6-2 and next faces Sharapova.

Patty Schnyder won a Swiss struggle as she took a 3-2 lead in her career rivalry with Martina Hingis after a 6-1, 6-7 (4/7), 6-3 win which puts her up against Petrova.

"I'm always nervous when I play her, and winning is always extra special," said the 11th seed, a semi-finalist in 2006. "We're both very ambitious. To beat her feels great.

"The third set really tough for me, mentally and physically," Schnyder added. "I was getting tired but when I got the break I knew I had a chance to win.

"It was a great fight like we expected."