Clijsters and Henin will play each other for the 25th time -- but
the first time in a Grand Slam since 2006. Their rivalry stands at
12-12 and has become friendlier over the years.
"It's obviously not the same as in the beginning," Clijsters
said. "We've definitely grown up. We've had great times together
playing Fed Cup and just messaging each other on phones, teasing
each other, fun, you know, relax. I think that's how I would have
liked it to have always been."
Both Belgians have mounted career comebacks from retirement.
Clijsters last played at Wimbledon in 2006, Henin in 2007. Henin
has seven Grand Slam titles and Clijsters two, but neither has won
the Wimbledon crown.
Clijsters won their previous meetings this year in Brisbane
and Key Biscayne.
Williams, a five-time Wimbledon champion, was down 3-1 in the first set Friday before taking control and ousting the 26th-seeded Russian.
Kleybanova put up a good fight in the set, which turned into a slugfest from the back of the court.
Williams took a tumble in the last game as she slipped on the grass, but appeared unscathed.
Williams will play the winner of the match between Australia's Jarmila Groth, who defeated German Angelique Kerber 6-3, 7-5 for a berth in the quarterfinals.
Seeded No. 1, the Williams sisters are seeking their fifth consecutive Grand Slam doubles championship and 13th overall. They are seeded 1-2 in singles and still in contention for that title.
Information from The Associated Press was used in this report.