PARIS (Reuters) - Jelena Jankovic goes into Thursday's French Open semi-final against Ana Ivanovic with both form and fitness weighing heavily against her.

While the duo will contest a Serbian showdown, the other semi will be an all-Russian affair between comeback queen Dinara Safina and fourth seed Svetlana Kuznetsova.

Second seed Ivanovic will walk on to Court Philippe Chatrier as fresh as a daisy after conceding just 20 games in her five matches so far as she seemingly walks towards a first grand slam title with total assurance.

Jankovic, meanwhile, has also not lost a set at Roland Garros but her progress has been, by comparison, tortuous.

Treated for a wrist injury in her second-round match against Marina Erakovic, she also needed medical attention on a stiff neck and shoulder in the fourth round and made a dash home to Serbia before her quarter-final triumph to receive treatment.

The pair have met six times and Jankovic has prevailed only once in Los Angeles two years ago, and Ivanovic won in straight sets in their only previous meeting on clay.

But what Jankovic lacks in fitness and previous form, she more than makes up for it in self belief.

"My dream is to become number one in the world, and now I'm very close. So I will try my best, and hopefully I can do it," said the third seed, who will replace Maria Sharapova at the top of the pile if she takes the title.

"I had troubles in the past against her, but I don't think we played on clay many times. So it's a different game and it's different circumstances, so I think it will be a completely different match. So we will see how it will goes this time."

Justine Henin's crown as queen of Roland Garros is looking like an increasingly perfect fit for Ivanovic.

DESTROYED OPPOSITION

She has destroyed the opposition this fortnight, clubbing winners off both wings and appears the clear heir apparent to the now retired four-times champion from Belgium.

Both born in Belgrade 2-1/2 years apart, the two Serbs have never developed a close friendship because of their different coaching decisions, but Ivanovic is aware of her rival's strengths.

"She's a tough opponent and she defends really well. (I need to) step in and be aggressive and play my game," said Ivanovic, who also has Sharapova's top spot in her sights.

"Every match is a new match, a new experience, and I just have to keep playing like I played so far."

Safina will be hoping she also keeps playing the way she has, although perhaps with a little less drama.

The 13th seed is proving to be one of the greatest comeback artists on the grand slam stage after she survived a match-point for the second successive match to reach the last four of a major for the first time.

Marat Safin's younger sister followed up her remarkable victory over world number one Maria Sharapova with an equally astonishing win over seventh seed Elena Dementieva on Wednesday.

"First time in a semi-final so you can say that it's a breakthrough. I just hope I keep on going," said Safina.

She will, however, run into the woman tipped by the now retired Henin as champion-elect who has yet to drop a set and has spent considerable less time on court than Safina.

"It's going to be very tough match. Dinara is playing very well on clay court," said the 2006 runner-up.

"She won Berlin, she won two matches here with match balls down. She has too many lives, so I have to be careful with her."

(Additional reporting by Pritha Sarkar; Editing by Padraic Halpin)