Stuttgart:Flavia Pennetta upset defending champion Jelena Jankovic 2-6, 6-4, 6-4 at the Porsche Grand Prix on Friday and lined up a semifinal with top-ranked Dinara Safina.
Safina, playing her first tournament since becoming No. 1 in the world less than two weeks ago, beat eighth-seeded Agnieszka Radwanska 6-4, 6-2.
Second-seeded Elena Dementieva beat Marion Bartoli 6-2, 4-6, 6-3 to make the last four at the Stuttgart tournament for the third time. She will play four-time semifinalist Svetlana Kuznetsova, who defeated Gisela Dulko of Argentina 6-3, 6-2.
Safina became the third Russian to reach the last four with an easy win over her Polish opponent.
"It feels great, I am really enjoying it here," she said.
Jankovic, seeded third, came into the match with a 7-0 record on clay this season after winning her first title of the year in Marbella, Spain.
But Pennetta, an unseeded Italian, proved to be the steadier player from the baseline and hit 32 winners, twice as many as Jankovic.
"I was nervous at the beginning but at the start of the second set I started pushing more and using my forehand more," Pennetta said.
Jankovic won the first set with relative ease but Pennetta raised her game in the next two as the erratic Serb struggled to find her range.
"I started to be more aggressive and to play more down the line, not crosscourt. She got tired and she started to make more mistakes," Pennetta said.
Pennetta had lost her first five matches against Jankovic but beat her in their last meeting in Zurich in October, when Jankovic was ranked No. 1 in the world.
Jankovic went through a slump at the start of the year, which she attributed to a change in her fitness regime, and has dropped to No. 4.
"My game fell apart. In the second set, my level started going down. I let her play her game," Jankovic said. "I've been having a cold this week and I got tired."
Jankovic said she was looking forward to playing outdoors in Rome next week, where she will be seeking her third title.
"I am not losing my confidence because of this loss," she said.
The Stuttgart tournament used to be played on a hard surface, but has become the first indoor event on clay on the circuit.
Dementieva, who won the Olympic gold medal last year in Beijing, needed four match points to finish off Bartoli, hitting a deep backhand on the line to clinch her third consecutive victory over the Frenchwoman and improve to a 5-2 career record.
"I am very glad I was able to finish strongly," Dementieva said. "It was a very emotional match for both of us."
Dementieva was up a break in the second set and led 4-3, but Bartoli, the 2007 Wimbledon runner-up, won the next three games to even the score at one set apiece.
Bartoli, who plays two-handed from both sides, wasted one set point but got some help from Dementieva when the Russian double-faulted to give Bartoli another chance.
Dementieva was more consistent in the third, while Bartoli mixed big winners with mistakes on straightforward shots.
The Russian raced to a 4-0 lead, but then nearly threw the match away as Bartoli won the next three games.
Dementieva recovered in time and was two wins away from capturing her third title of the year.