Agnieszka Radwanska snuck by Sara Errani 7-6 (1), 7-5 to reach the semifinals of the Rogers Cup.
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TORONTO (AP) -- Agnieszka Radwanska defeated Sara Errani 7-6 (1), 7-5 Friday to reach the semifinals of the Rogers Cup.

She'll be joined in the final four by fourth-seeded Li Na of China who defeated Dominika Cibulkova of Slovakia 7-6 (1), 6-2.

Li, last year's finalist, needed 96 minutes to get by the world No. 20-ranked Cibulkova, who came into the tournament on a roll with a recent title victory at Stanford over Radwanska.

Li broke to make it 6-5 in the first set, taking the game with a blazing cross-court winner, but couldn't hold and needed a tiebreak to win the set. She cruised through the second set en route to her first semifinal berth since losing at Stuttgart in April.

Radwanska gained a measure of revenge against Errani, an Italian seeded fifth. Errani eliminated Radwanska in the quarterfinals of this year's French Open.

In the first set, Radwanska took the tiebreaker with a drop-shot volley that forced a wide return from Errani. In the second set, the Pole won when Errani returned long on double match point.

The two players again traded breaks in the second until Radwanska held serve at 6-5 when Errani returned long on double match point.

Radwanska closed it out in just over two hours, avoiding any repeat of their 2012 meeting at the WTA Championship - an epic three-and-a-half hour, three-set victory for Radwanska.

Radwanska will take on the winner of the late match between top-seeded American Serena Williams and Magdalena Rybarikova of Slovakia. Defending champion Petra Kvitova of the Czech Republic was to meet Romania's Sorana Cirstea in the other quarter-final.

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