US Open: Serena Williams, Li Na, Victoria Azarenka and Flavia Pennetta take centre stage
It is ladies' semi-finals day as red-hot Serena Williams takes on Li Na while Victoria Azarenka battles Flavia Pennetta.
Last Updated: 07/09/13 8:25am
Williams has been in imperious form since the start of the tournament in New York, dropping only 13 games in five matches after whitewashing Carla Suarez Navarro in the quarter-finals.
The 31-year-old has only lost five matches since her surprise first-round loss to Virginie Razzano in last year's French Open. Since that defeat she began working with Patrick Mouratoglou.
Sixth seed Li has always given Williams a closely-fought contest, although it is the American who has emerged triumphant in their past seven meetings.
The pair last met in the semi-finals at the Western & Southern Open in Cincinnati last month, where Williams booked her place in the final courtesy of a 7-5 7-5 success.
Williams also has a doubles match to contend with on Friday. She and sister Venus will battle it out against Czech Republic pair Andrea Hlavackova and Lucie Hradecka.
The second US Open semi-final sees second seed Azarenka take on surprise package Pennetta.
Belarusian Azarenka, who lost last year's final to Williams, comfortably saw off Daniela Hantuchova in the last eight.
Azarenka was due to take Pennetta at Wimbledon in June before a knee injury curtailed the second-round contest.
Pennetta is through to her first grand slam singles semi-final a year after having wrist surgery that kept her out of the game for six months.
The 31-year-old is aiming to become the first Italian player to reach a singles final at Flushing Meadows.
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