- US Open
Sharapova sets up Wozniacki showdown
Maria Sharapova scrapped her way to a 6-2 6-4 victory over Germany's Sabine Lisicki at the US Open to set up a last-16 clash with No.10 seed Caroline Wozniacki.
The French Open champion hit eight double-faults in an error-strewn performance from both players, racking up 56 unforced errors between them.
"You have no choice but step it up when it counts if you want to continue and ultimately be the champion of this event," said Sharapova, who insisted she was not overly concerned about her performance.
Up next for the former champion is 2009 finalist Wozniacki, who handily beat Andrea Petkovic 6-2 6-3 on Grandstand.
"Every match I kind of get into a better groove out there and I'm playing better," Wozniacki said before reflecting on facing an opponent she hasn't beaten since 2011.
"It's nice to be through to the fourth round again. It's going to be another tough one, but I'm excited about it."
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Sara Errani moved into the last 16 after battling her way past Venus Williams in a thrilling encounter on Friday afternoon.
Williams responded after failing to win a single game in the first set by reeling off six straight games to take the second set.
She then had a chance to serve for the match in the third set, up 5-3, but could not finish off Errani, who triumphed 6-0 0-6 7-6(5).
Williams twice came back from down a break in the third but was undone by too many unforced errors. She made 52 in the match.
"Even if I won the first set 6-0, she's an amazing player," Errani said in an on-court interview.
Errani, seeded 13th, next faces world No.121 Mirjana Lucic-Baroni, the qualifier who stunned second seed Simona Halep 7-6(6) 6-2. The 32-year-old Lucic-Baroni hadn't made a grand slam round of 16 since 1999.
Halep, the runner-up at the French Open and a semi-finalist at Wimbledon, made seven-double faults and hit only 17 winners. Halep was trying to make the fourth round at Flushing Meadows for the second year in a row.
But Lucic-Baroni outplayed her, hitting 31 winners, to get back to the fourth round at a grand slam tournament for the first time since she was a Wimbledon semi-finalist as a teenager in 1999.
Elsewhere, Peng Shuai beat another seeded player in Roberta Vinci 6-4 6-3 to reach her second straight grand slam round of 16, two days after upsetting fourth seed Agnieszka Radwanska.
Peng had gone two years without going past the second round at a grand slam before her Wimbledon run this summer, where she lost to eventual champion Petra Kvitova in straight sets.
World No.39 Peng now faces either 14th seed Lucie Safarova or 22nd seed Alize Cornet as she bids to reach her first grand slam quarter-final.
Jelena Jankovic also progressed with a comprehensive 6-1 6-0 win over Johanna Larsson.