Agnieszka Radwanska, the world's second-ranked woman, defeated No. 30 Jelena Jankovic in two sets on Saturday to advance to the fourth round of the 2012 U.S. Open. Radwanska was yet to really be challenged in the tournament in the earlier rounds, although Jankovic changed that on Saturday morning.

Radwanska won the first set 6-3. She then won the second and decisive second set 7-5. Jankovic had more winners than her opponent did (23 to 15), but it was 37 unforced errors that cost her the match. Radwanska's serve topped out at 107 mph, while Jankovic's was even harder at 110.

With the win in-hand, Radwanska will now face Roberta Vinci in the fourth round. Vinci, who is ranked 20th in the world, defeated Dominika Cibulkova in two sets to advance on Saturday.

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