• WTA

Sluggish Serena sets up Li Na clash

Serena Williams recovered from a horror first set to book her place in the quarter-finals of the Sony Open on Monday.

Williams, chasing her 48th career title at the age of 31, struggled for accuracy against world No. 14 Dominika Cibulkova as the first set raced from her grasp in quick time. However, the top seed battled back to take the next two for a 2-6 6-4 6-2 victory.

The players had only met on one previous occasion, with Williams successful in straight sets at Wimbledon in 2010. On that occasion it was the American who stormed through the first set, winning it 6-0, but Monday in Miami was a different story.

A string of unforced errors flew from the Williams racket as she won only two points behind her second serve in the opening stanza. Cibulkova broke three times to take control, winning nearly double the amount of points claimed by her rival.

The momentum shifted in the second, with Williams finding seven aces as her serve vastly improved. She still suffered one break, but now had the platform from which to attack as she twice penetrated the Cibulkova delivery to level the match.

The players exchanged three service breaks at the start of the third, two for Williams as she went ahead for the first time in the contest. Another followed as she eventually closed out the match in just shy of two hours.

Williams will now face Li Na in the quarter-finals, after the fifth seed beat Garbine Muguruza 7-6(6) 6-2. Li was asked plenty of questions by the 19-year-old world No. 73 in the first set, but the tiebreaker proved crucial as Muguruza's resistance faded thereafter.

Agnieszka Radwanska, the fourth seed, was another to advance on Monday, beating Sloane Stephens 4-6 6-2 6-0. Kirsten Flipkens, Jelena Jankovic and Roberta Vinci also progressed in the competition.

Maria Sharapova was in fine form as she progressed to the last eight with a 6-2 6-2 win over Klara Zakopalova. Up next for the No. 3 seed is a clash with Sara Errani who battled from a set down to beat Ana Ivanovic 1-6 6-4 6-2.

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