Svetlana Kuznetsova beat Hungarian teenager Agnes Szavay 6-1 6-4 to reach the U.S. Open semi-finals on Wednesday and believes she is a better player than when she won the title in 2004.
The Indian ace beat USA's Laura Granville 6-3, 7-5 in the second round at the US Open.
The third seeded Indian ace easily beat Olga Govortsova of Belarus at the US $175,000 WTA Tier III event.
Maria Sharapova made it to her maiden semi-finals of the French Open by beating fellow Russian Anna Chakvetadze 6-3, 6-4.
Justine Henin beat Italian Mara Santangelo 6-2, 6-1 in the quarterfinals of the Warsaw Cup.
Henin and Williams have met eight times in their careers but Saturday's clash will be the first since the muscular American won a semi-final meeting with the Belgian at Wimbledon nearly four years ago.
They needed iron willpower to stagger through scrappy quarter-finals on Wednesday and set up a heavyweight meeting in the last four.
The Russian overcame a groin injury to reach her first Kremlin Cup final beating Czech teenager Nicole Vaidisova.
Second seed Maria Sharapova crushed defending champion Mary Pierce 6-2 6-3, setting up a last four clash with Patty Schnyder of Switzerland, who beat number four Elena Dementieva 6-4 6-3.
The Russian will meet Patty Schnyder, who beat number four Elena Dementieva, in the semi-finals of the Acura Classic.
However, the Indian ace and her partner South African Liezel Huber, entered the doubles quarter-finals of the Acura Classic.
The Indian ace was pushed down by Russia's Anna Chakvetadze and Spain's Anabel Medina Garriques, who occupy the 32nd and 33rd places respectively.
Lindsay Davenport beat Russian Anna Chakvetadze 6-3, 6-3 to reach the final of the New Haven Open
The American will regain the world number one ranking from Russian Maria Sharapova if she reaches the final.
Mirza teamed up with Russian Anna Chakvetadze to beat Kristina Brandi of Puerto Rico and Nana Miyagi of Japan.
The fine run at the WTA event in Stanford fetched the Indian ace 190 points and took her four rungs up.
Top seed Anna Chakvetadze defeated India's Sania Mirza 6-3, 6-2 to win her first Stanford classic title.
