NEW YORK (AP) In a U.S. Open women's tournament filled with surprises, Maria Sharapova heads into the fourth round as the only major champion in her half of the bracket.
Sharapova owns five major titles, including at Flushing Meadows in 2006 and at the French Open in June, and the other seven players remaining on her side of the field have played in a grand total of three Grand Slam finals, going 0-3.
One of those runners-up is Caroline Wozniacki, a 2009 U.S. Open finalist who is Sharapova's opponent Sunday, with the winner heading to the quarterfinals.
Both have been ranked No. 1. Sharapova is seeded fifth in New York; Wozniacki 10th.
''She's really raising her level to where she wants it to be. Although we haven't played in a while, we have played against each other many times. No secrets on our games,'' said Sharapova, who is 5-2 against Wozniacki. ''We've been on the tour for many years, so I expect a tough match, a physical match. She always makes you hit a lot of balls, gets a lot of balls back.''
Among the top six seeded women, Sharapova and No. 1 Serena Williams were the only two to get to the round of 16.
No. 2 Simona Halep, No. 3 Petra Kvitova, No. 4 Agnieszka Radwanska and No. 6 Angelique Kerber all failed to make it out of Week 1.
''You always have favorites going into the tournament. The reason there's so many players is because we have to go out and win those matches and compete,'' Sharapova said. ''There's a reason everybody puts the net up in the morning.''
Here are some other things to watch on Day 7 at the year's last Grand Slam tournament:
WHITHER THE WEATHER?: Not a drop of rain interrupted play through the first six days at the U.S. Open this year. That could change Sunday, when the forecast called for scattered showers.
Wet weather has been a big issue at the year's last Grand Slam tournament recently: Every year from 2008-12, the men's final wound up being played on a Monday instead of its scheduled Sunday, thanks to rain.
The U.S. Tennis Association is in the midst of a major renovation project that is expected to cost about half a billion dollars and includes installing a retractable roof on Arthur Ashe Stadium in time for the 2016 U.S. Open.
LONG WAIT: Sara Errani says she remembers seeing Mirjana Lucic-Baroni training at a tennis academy about 15 years ago. On Sunday, they'll play each other with a U.S. Open quarterfinal berth at stake.
The 13th-seeded Errani, the 2012 French Open runner-up, now faces Lucic-Baroni, a 32-year-old from Croatia who is ranked 121st and needed to go through qualifying to make her way into the main draw. Errani eliminated Venus Williams in the third round, when Lucic-Baroni stunned second-seeded Simona Halep.
The last time Lucic-Baroni reached the fourth round at a Grand Slam tournament was at Wimbledon all the way back in 1999, when she made it to the semifinals.
But since then, family issues and injuries sidetracked her career. She did not enter a major tournament for nearly eight years, from U.S. Open in 2002 until Wimbledon in 2010.
''In a way, I know I sound like and I feel like a little kid, like this is the first time ever happening,'' Lucic-Baroni said. ''I love the feeling.''
GOFFIN EYES SURPRISE: Wimbledon semifinalist Grigor Dimitrov, who is seeded No. 7 in New York, faces an intriguing matchup Sunday night in Arthur Ashe Stadium. His third-round opponent is 56th-ranked David Goffin of Belgium, who is enjoying quite a run of success lately.
Since losing to Andy Murray in the first round at Wimbledon in June, Goffin has gone 27-1. That included a 25-match winning streak - and a stretch of 36 consecutive sets won - mainly accomplished at tournaments in tennis' minor leagues. But Goffin did beat 32nd-seeded Joao Sousa in straight sets in the U.S. Open's second round.
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