Serb Jelena Jankovic and Russian Dinara Safina, the top seeded players left in the Family Circle Cup, cruised into the last 16 on Wednesday.

Unseeded threats Venus Williams and Frenchwoman Tatiana Golovin were also in devastating form in the Tier I claycourt tournament that suffered from occasional rain delays.

Peng Shuai of China pulled off the upset of the second round when she rallied to stun sixth seeded Swiss Patty Schnyder 1-6 6-3 6-3.

Jankovic, the second seed and world number nine, thrashed Russian qualifier Anastassia Rodionova 6-1 6-1 while 12th ranked fourth seed Safina beat Eleni Daniilidou of Greece 6-3 6-4 .

"I thought I played quite well for my first (match) here, especially with it starting to rain a little bit," said Jankovic. "It was a little bit slippery but I did my best."

She will now play Italy's Mara Santangelo in the third round while 12th ranked Safina faces Spain's Lourdes Dominguez.

Williams had an easy time against Russia's Vasilisa Bardina, winning 6-2 6-1 in 49 minutes. The American suffered a wrist injury early this year and did not take her 2007 tour bow until winning the Memphis title on February 24.

Golovin, the world number 19 who won her first tour tournament last week at Amelia Island, ousted American veteran Jill Craybas 6-0 6-1.

Seventh seed Ana Ivanovic of Serbia, China's Zheng Jie, Austria's Sybille Bammer, Spain's Anabel Medina and Russia's Vera Zvonareva also reached the last 16 on Wednesday to join China's Na Li, who got through on Tuesday.

Top seed Nicole Vaidisova lost on Tuesday in the second round to Michaella Krajicek of Netherlands and third seed Serena Williams retired with a right groin strain while trailing Taiwan's Yung-Jan Chan 5-3 in the first set.

"The first tournament on clay and we're sliding," said Venus, who would have faced her sister in the third round but now plays Chan on Thursday. "It's just bad luck."