Stuttgart, May 2 (Inditop) Flavia Pennetta of Italy did it again to Jelena Jankovic with a 2-6, 6-4, 6-4 win as the Serbian title holder crashed out of the Porsche Grand Prix quarter-finals.

The 14th-ranked Pennetta clinched the comeback upset win in 1 hour 58 minutes against a tiring and erratic third seed Jankovic Friday.

Pennetta, 27, lost the first five matches against Jankovic but then beat her the last time they met, in Zurich last autumn, less than two weeks after Jankovic had claimed the world number one spot with the Stuttgart title in October 2008.

“I am very happy about the match. I was nervous before the start of the match. I was more aggressive from the second set onwards and moved her around more. She started to feel more pressure,” said Pennetta.

The Italian now meets current world number one Dinara Safina of Russia, who defeated Poland’s eight seed Agnieszka Radwanska 6-4, 6-2 in 73 minutes.

Olympic champion Elena Dementieva overcame stiff resistance from Marion Bartoli, 6-2, 4-6, 6-3, for an all-Russian semi-final against fifth-seeded Svetlana Kuzentsova, a 6-3, 6-2 winner over unseeded Argentine Gisela Dulko.

Jankovic was hoping to regain her 2008 form at the Stuttgart tournament, which is now held in April on clay instead of October on hard court.

She was in full command against Pennetta in the first set, but the Italian, who had ousted six seed Nadia Petrova Thursday, roared back.

The Italian squared the sets with a ninth-game break and then got the vital advantage for 4-3 in the final set. She served out the match in the 10th game when Jankovic hit a groundstroke wide.

“The difference came somewhere in the beginning of the second set. My level went down and I let her dominate,” said Jankovic, adding that she had suffered from a cold recently and tired in the end.

But she vowed ahead of the upcoming events highlighted by the French Open Grand Slam: “This defeat means nothing to me. I am not losing my confidence.”

Safina, who is playing her first tournament since earning the top ranking last week, failed to serve out the first set against Radwanska at 5-3, but then broke to take the set. She then won five straight games from 2-1 down in the second to clinch victory.

“It feels great. I am very happy to be in the semi-finals and really enjoy playing here,” said Safina.

The second-seeded Olympic champion Dementieva squandered a one-break lead twice in the second set and almost threw away a 4-0 advantage in the third before beating Bartoli in 2:17 hours after the French had fought back to 4-3.

“This was my best match so far, it was a good fight from the first ball to the end,” said Dementieva, whose was also in the Stuttgart semis in 2002 and 2005.

Kuznetsova is in the Stuttgart semis for the fourth time (2004, 2006, 2007, 2009) and holds a slim 5-4 lead in the series with Dementieva.

After being stretched to long three-setters in the opening rounds Kuznetsova made short work of Dulko to take a 3-2 lead in their series. A break in the second game was enough to take the first set and Kuznetsova never looked back after a break for 2-1 in the second.