When and where: Semi-final action gets underway at the Internazionali BNL d'Italia at 6 a.m. ET. A live stream of the full day's play will be available thorugh the tournament website, via a subscription to Tennis TV, while coverage will also be provided by the Tennis Channel. A live stream of the mens' semi-finals will also be accessible via ESPN3,

Preview: With the French Open now just over a week away, the leading players on both the men's and women's tours have been refining their clay-court form in Rome this week.

And both draws have provided stellar semi-finals that will provide significant clues ahead of the year's second grand slam at Roland Garros.

Saturday's match-ups are undeniably highlighted by the evening match, which pits Novak Djokovic and Roger Federer. With the Swiss claiming the title in Madrid last week and moving above Rafael Nadal in the ATP rankings, this semi-final is now a battle of the top two players in the world.

And Federer is arguably in the best form of anyone on tour right now. After taking full advantage of his rivals' problems on the blue clay in Spain, Federer has progressed to the Semi-finals in Rome without the loss of a set.

Having beaten the Serbian in last year's French Open semi-finals, a win in Rome would give Federer a massive psychological edge heading to Paris.

Tomorrow, I've got a chance against Djokovic, Federer said, according to the ATP Tour website. I'm looking forward to that match. It's another night session. I'm happy I'm playing so well on the court.

The first men's semi-final is no mere warm-up either. In the late afternoon sun, Rafael Nadal will be looking to rediscover his dominance on clay as he goes up against sixth seed David Ferrer. But, while Ferrer never gives any opponent an easy ride, Nadal holds an impressive 14-4 record against the 30-year-old and has not been beaten on clay by his fellow-Spaniard since 2004.

The last meeting between the pair came in the final of Barcelona last month, with Nadal winning in two tight sets.

As well as the ATP Masters 1000 event taking place this week in the Italian capital, the WTA tour is also in town for one of the biggest stops on their calendar.

Saturday's play begins with an eagerly anticipated duel between 13-time time grand slam winner Serena Williams and last year's French Open champion Li Na. Since that memorable win, Li has struggled to live up to her new found fame as Asia's first-ever grand slam winner. But after making only her second semi-final of the year, the 30-year-old is hopeful of creating a more consistent mind set as she heads to Roland Garros to defend her title.

On the tour nobody gives a match to you, Li said, according to the WTA Tour website. It's hard to stay at a high level all the time. In just a second your mind can go somewhere else, and that can be a problem for me--I'm not worried about my forehand and backhand.

Li will certainly need all her focus is she is to take out a resurgent Serena Williams. After demolishing world No. 1 Victoria Azarenka to claim the title in Madrid last week, Serena is up to up to sixth spot in the rankings, and climbing. Undefeated on clay this year, the American has also made herself a firm favorite to claim a second French Open crown.

In the other women's semi-final Maria Sharapova will take on German Angelique Kerber. Following her topsy-turvy three-set defeat of Wimbledon champions Petra Kvitova in the quarter-finals, Kerber has assured herself a place among the world's top 10 for the first time, whatever happens on Saturday.

But Sharapova claimed an impressive scalp of her own in the last round, taking out Venus Williams in a tough straight sets win. The Russian will be seen as favorite, but left-hander Kerber won the last time the pair met, earlier this year indoors in Paris.