Rome, Italy (SportsNetwork.com) - World No. 1 great Serena Williams and Australian Open champion Li Na were a pair of easy winners, while previously red-hot Maria Sharapova lost to a fellow former top-ranked star Thursday at the $2.6 million Italian Open.
The reigning Rome champion Williams waltzed past fellow American Varvara Lepchenko 6-1, 6-2 in the night session on the clay at Foro Italico.
Williams beat Victoria Azarenka in last year's final for her second career title in the "Eternal City."
The 32-year-old's quarterfinal opponent on Friday will be unheralded Chinese Zhang Shuai.
Eleventh-seeded Serb Ana Ivanovic took down the eighth-seeded two-time Rome champion Sharapova 6-1, 6-4 on Day 4.
Ivanovic is now 3-8 lifetime against Sharapova, who prevailed in a final in Stuttgart between the two just last month. The Russian also topped the Serb in a bout here in Rome two years ago.
Sharapova was seeking her third title in three events, having recently claimed championships in Stuttgart and last week in Madrid. She was a perfect 12-0 on clay this year and 48-3 on the dirt since 2012, with her only losses coming at the hands of Serena Williams, prior to Thursday.
The 27-year-old Sharapova was the back-to-back Rome champion in 2011 and 2012 and lost to Williams in last year's marquee finale.
Meanwhile, the second-seeded 2012 Rome runner-up Li eased past former U.S. Open champion, former Roland Garros runner-up and 2011 Rome finalist Samantha Stosur 6-3, 6-1 at this French Open tune-up.
Also on Thursday, third-seeded Polish star Agnieszka Radwanska disappointed the Italian faithful by dismissing former French Open champ Francesca Schiavone 6-4, 6-1, sixth-seeded former No. 1 Jelena Jankovic knocked out 12th-seeded Italian Flavia Pennetta 6-2, 6-3 and 10th-seeded former Roland Garros finalist Sara Errani, of Italy, got past Czech qualifier Petra Cetkovska 6-4, 7-6 (7-3). Jankovic titled here back-to-back in 2007 and 2008 and was the runner-up in 2010.
In a matchup of non-seeds, the aforementioned Zhang outlasted American qualifier Christina McHale 6-2, 4-6, 6-2.
Friday's other quarterfinals will pit Li against Errani, Radwanska versus Jankovic and Ivanovic against 13th-seeded Spaniard Carla Suarez Navarro.