Mason, Ohio: Venus Williams fought back from a set down to beat South Africa's Chanelle Scheepers 2-6, 6-3, 6-2 as the top seeds advanced with little trouble at the Cincinnati Open on Wednesday.
Williams will now meet Italian Sara Errani for a quarter-final berth following the seventh seed's 6-4, 6-4 win over Slovakian Daniela Hantuchova.
For the second successive day, Williams needed three sets but she was glad with the way she recovered from a rusty opening. "I made so many errors. She's [Scheepers] one of those players that puts a lot of balls in the court, makes you play a lot of shots and I wasn't getting them in the court. It was good to turn it around," said Williams.
Top seed Agnieszka Radwanska defeated Sweden's Sofia Arvidsson 6-4, 6-3 to book her place in the third round. Pole Radwanska, playing in her first premier event as a top seed, said she was pleased with how she had settled in to the event.
"The first match is always the most difficult. Every week we play on different surfaces with different balls and in different conditions. I'm just happy I went through, especially in two sets, because of the heat," she said.
Radwanska will next face Sloane Stephens after the American beat fellow wildcard entrant Camila Giorgi of Italy 6-2, 6-1 in an hour.
Her sister Urszula Radwanska, now ranked 46th in the world, progressed to the third round after Kazakh Yaroslava Shvedova retired due to "heat illness".
Denmark's Caroline Wozniacki needed just 59 minutes to dismiss Kazakh Sesil Karatantcheva 6-1, 6-0 in a totally one-sided affair. In the third round, Wozniacki will face Russian Anastasia Pavlyuchenkova, who swept aside Germany's Julia Goerges 6-3 6-0.