Poland's Agnieszka Radwanska defeated Russian Anastasia Pavlyuchenkova in the third round of the 2013 U.S. Open in New York, and China's Na Li advanced past Laura Robson in Friday's early action.
Radwanska, the tournament's No. 3 seed, won 6-4, 7-6(1) but in general, neither player could quite get a handle in the 44-minute first set nor the 73-minute long second. Both played serves well and the opponents combined for only five aces.
Pavlyuchenkova recorded 41 unforced errors to Radwanska's 15, yet stayed in the game by attacking at the net to the tune of scoring on 19-of-29 net point opportunities. But it wasn't enough. Radwanska's patience and mistake-free play eventually was too much.
Radwanska will face the victor of No. 16 seed Sabine Lisicki of Germany and Russia's Ekaterina Makarova, who is the 24th seed.
Earlier on Friday, the fifth-seeded Li made a quick job of closing out her first set against Robson. There, Robson fought from behind all along -- she didn't have a break point opportunity and had only one chance to score on a net point. Meanwhile, Li won all 11 of her first serve points. But it took a little more arm grease from Li to put away the No. 30 seed.
The second set lasted 52 minutes as both players accumulated 15 unforced errors each, but by the end of the match, Li had 11 aces to Robson's zero. Robson ended up losing by failing to control her serves. Only 32 of her 62 serves were in, and she converted only half of her first serves into points.
Li will face the winner of No. 9 seed Jelena Jankovic and Japan's Kurumi Nara.