MASON, Ohio (AP) -- Kim Clijsters is turning Cincinnati into her kind of town.
The defending US Open champion reached the semifinals at the Cincinnati Open on Friday, beating Italy's Flavia Pennetta 7-6 (6), 6-4 in oppressive afternoon heat. The fourth-seeded Clijsters will next face Serbia's Ana Ivanovic.
No. 10 Maria Sharapova also reached the semifinals, beating France's Marion Bartoli 6-1, 6-4 in the evening match. She'll play fellow Russian Anastasia Pavlyuchenkova.
Clijsters is the highest remaining seed. Five of the top eight were eliminated on Thursday. Serena and Venus Williams dropped out with injuries before the tournament began.
That left center court to Clijsters, who seems to like the place.
Clijsters returned to tennis in Cincinnati last year, reaching the quarterfinals after a two-year break to start a family and get recharged. The 27-year-old Belgian reached the quarterfinals in Cincinnati and found her touch. A few weeks later, she won the US Open.
This year, she took a break from tournament play after Wimbledon and arrived in town hoping to use Cincinnati as a springboard again.
So far, the hard courts have been agreeable.
"There's moments when it's good, moments when it's not good,'' she said. "Each match has gone better. That's what I'm looking for.''
Clijsters passed her toughest test of the week, making a few more shots than Pennetta in a match close throughout. She hit a service winner to go up 7-6 in the tiebreaker, and Pennetta sailed a forehand wide to settle the sweaty first set.
Clijsters went to her seat and squirted cold water over her hair, trying to get a little relief. On-court temperatures have registered 120 degrees the past couple of days, with oppressive humidity that made it tough to breathe after long points.
The heat had a lot to do with setting up her semifinal opponent.
Down 5-1 in the opening set of her quarterfinal match against Yanina Wickmayer, Pavlyuchenkova started to think about doing better in the second set. Turned out the first one was far from over.
Taking advantage of a heat-drained opponent, the 19-year-old Russian rallied for a 7-5, 3-6, 6-1 win that extended one of the best stretches of her career.
"It was really tough conditions today,'' Pavlyuchenkova said.
Her opponent used so much energy getting ahead 5-1 in the first set that she began feeling the strain. Her legs got a little shaky. Her game fell apart.
"I started off really well in the first set, got really tired after that,'' Wickmayer said. "And she came back and put up a great fight.''
Pavlyuchenkova is coming off a title at Istanbul. Asked if she has the energy to extend her streak of nine straight wins, she said, "I don't know. We'll see tomorrow.''
Sharapova will be rested. Bartoli had only seven points and eight unforced errors while falling behind 5-0 in the first set. Sharapova has dropped only one set in four matches this week.
"I was playing at a very high level the whole match,'' Sharapova said. "Many things were going really well for me.''
The last remaining qualifier melted away at the $2 million Western & Southern Financial Group Women's Open.
Akgul Amanmuradova pulled off the biggest upset of the week, knocking off top-seeded Jelena Jankovic in two sets on Thursday. It was the biggest career win for the 26-year-old Amanmuradova, who is ranked No. 114 and had never beaten a Top-10 player.
A day later, she never had a chance against Ivanovic, losing 6-1, 6-3 in only 56 minutes.
"I was really tired from the whole week and all the matches,'' Amanmuradova said. "So obviously my serve speed broke down a little bit, which makes a lot of difference on this level.''