Nick Kyrgios, left, received further punishment from the ATP this week for sledging Stan Wawrinka, right. Thus, Kyrgios is sure to be closely monitored in New York.
The Kyrgios fallout —
Nick Kyrgios, left, received further punishment from the ATP this week for sledging Stan Wawrinka, right. Thus, Kyrgios is sure to be closely monitored in New York.
Clive Brunskill/Getty Images Europe/Getty Images
Kyrgios has faced controversy throughout the year and at Wimbledon was fined $9,500 for two offenses. He was also accused of tanking, which he denied.
The Kyrgios fallout —
Kyrgios has faced controversy throughout the year and at Wimbledon was fined $9,500 for two offenses. He was also accused of tanking, which he denied.
Minas Panagiotakis/Getty Images
Wawrinka will be seeking his second major title of the year after winning the French Open in June.
The Kyrgios fallout —
Wawrinka will be seeking his second major title of the year after winning the French Open in June.
Clive Brunskill/Getty Images Europe/Getty Images
Rafael Nadal is struggling. He hasn't made the semifinals at any major this year and lost early -- for him -- at warmup tournaments in Montreal and Cincinnati.
Nadal's tribulations —
Rafael Nadal is struggling. He hasn't made the semifinals at any major this year and lost early -- for him -- at warmup tournaments in Montreal and Cincinnati.
Maddie Meyer/Getty Images North America/Getty Images
Nadal knows what it's like to win at the U.S. Open, having triumphed twice, including on his last visit in 2013.
Nadal's tribulations —
Nadal knows what it's like to win at the U.S. Open, having triumphed twice, including on his last visit in 2013.
Al Bello/Getty Images North America/Getty Images
The men's favorite is world No. 1 Novak Djokovic. He's won two majors this year and been in all three grand slam finals. If he wins in New York, he would reach double digits in grand slam crowns.
Djokovic going for No. 3 in '15 —
The men's favorite is world No. 1 Novak Djokovic. He's won two majors this year and been in all three grand slam finals. If he wins in New York, he would reach double digits in grand slam crowns.
Maddie Meyer/Getty Images North America/Getty Images
The heat affected Djokovic last year at the U.S. Open, when he was upset by Kei Nishikori. Nishikori would lose the final to Marin Cilic.
Djokovic goes for No. 3 in '15 —
The heat affected Djokovic last year at the U.S. Open, when he was upset by Kei Nishikori. Nishikori would lose the final to Marin Cilic.
Streeter Lecka/Getty Images North America/Getty Images
World No. 2 Simona Halep reached back-to-back finals in Toronto and Cincinnati after slumping at both Wimbledon and the French Open.
Halep's quest to find form at a major —
World No. 2 Simona Halep reached back-to-back finals in Toronto and Cincinnati after slumping at both Wimbledon and the French Open.
Rob Carr/Getty Images North America/Getty Images
Can she, however, play her best tennis in the pressure cooker environment of a grand slam? In her last four grand slams, she's made the quarterfinals once.
Halep's quest to find form at a major —
Can she, however, play her best tennis in the pressure cooker environment of a grand slam? In her last four grand slams, she's made the quarterfinals once.
Julian Finney/Getty Images Europe/Getty Images
This is Eugenie Bouchard's last opportunity to salvage her season, at least at the grand slams. Bouchard has won nine matches all season and her ranking has dipped from fifth last October to 25th.
Bouchard's shot at redemption —
This is Eugenie Bouchard's last opportunity to salvage her season, at least at the grand slams. Bouchard has won nine matches all season and her ranking has dipped from fifth last October to 25th.
Elsa/Getty Images North America/Getty Images
Maria Sharapova's late withdrawal with a knee injury ends prospects of her facing another semifinal against Serena Williams, who beat the Russian in her last outing at Wimbledon.
Sharapova on sidelines —
Maria Sharapova's late withdrawal with a knee injury ends prospects of her facing another semifinal against Serena Williams, who beat the Russian in her last outing at Wimbledon.
ADRIAN DENNIS/AFP/Getty Images
U.S. Open 2015: Five things to watch

Story highlights

Sharapova to miss season's final slam

The 2006 winner has not played since early July

Fellow Russian Daria Kasatkina replaces her

CNN  — 

World No. 3 Maria Sharapova has pulled out of the U.S. Open on the eve of the tournament due to an ongoing knee injury.

The 28-year-old revealed that she would be taking no part at Flushing Meadows on her official Facebook page.

“Unfortunately I will not be able to compete in this year’s U.S. Open,” Sharapova wrote.

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“I have done everything possible to be ready but it was just not enough time.

“To all my amazing fans, I will be back in the Asian swing in a few weeks and look forward to finishing the year healthy and strong.”

The 2006 U.S. Open winner has been out of action since her semifinal defeat to Serena Williams at Wimbledon in July.

The Russian, who was seeded third for the tournament, will be replaced by her compatriot Daria Kasatkina – who faces Australia’s world No. 37 Daria Gavrilova on Monday.

Sharapova was in the same half of the draw as defending champion Serena Williams, and potentially they could have faced each other in the semifinals.

Williams’ bid for a seventh U.S. Open title and tennis’ first calendar grand slam since Steffi Graf in 1988 starts Monday.

The world No. 1 faces 86th-ranked Russian Vitalia Diatchenko in the first round.

Serena Williams has been dominant at the majors, especially since last year's U.S. Open. But she has been beaten before at grand slams ...
Serena Williams has been dominant at the majors, especially since last year's U.S. Open. But she has been beaten before at grand slams ...
Mike Stobe/Getty Images for the USTA
The only time Williams lost in the first round of a grand slam came in 2012 against Frenchwoman Virginie Razzano at the French Open.
The only time Williams lost in the first round of a grand slam came in 2012 against Frenchwoman Virginie Razzano at the French Open.
PATRICK KOVARIK/AFP/AFP/Getty Images
Razzano, whose fiance died a year earlier, rallied from a set down and 5-1 down in a second-set tiebreak to pull off the shock win.
Razzano, whose fiance died a year earlier, rallied from a set down and 5-1 down in a second-set tiebreak to pull off the shock win.
PATRICK KOVARIK/AFP/AFP/Getty Images
The last player, meanwhile, to beat Williams in a grand slam final was Samantha Stosur at the 2011 U.S. Open.
The last player, meanwhile, to beat Williams in a grand slam final was Samantha Stosur at the 2011 U.S. Open.
Al Bello/Getty Images North America/Getty Images
Williams coming second in a grand slam final is rare: Her record in major finals stands at 21-4.
Williams coming second in a grand slam final is rare: Her record in major finals stands at 21-4.
Mike Stobe/Getty Images North America/Getty Images for USTA
Stosur is one of three players who have played Williams at least twice at a grand slam to have a winning record against the world No. 1. The other two are Justine Henin, seen here, and Jennifer Capriati.
Stosur is one of three players who have played Williams at least twice at a grand slam to have a winning record against the world No. 1. The other two are Justine Henin, seen here, and Jennifer Capriati.
JOE KLAMAR/AFP/AFP/Getty Images
One of Capriati's four wins over Williams took place at the US Open in 2004, when the latter was on the receiving end of at least one bad officiating call.
One of Capriati's four wins over Williams took place at the US Open in 2004, when the latter was on the receiving end of at least one bad officiating call.
DON EMMERT/AFP/AFP/Getty Images
Who was the last player to beat Williams at a grand slam? It's Razzano's countrywoman, Alize Cornet. She did it last year at Wimbledon.
Who was the last player to beat Williams at a grand slam? It's Razzano's countrywoman, Alize Cornet. She did it last year at Wimbledon.
Steve Bardens/Getty Images Europe/Getty Images
Garbine Muguruza toppled Williams at the 2014 French Open but Williams gained her revenge in July, defeating the Spaniard in the Wimbledon final.
Garbine Muguruza toppled Williams at the 2014 French Open but Williams gained her revenge in July, defeating the Spaniard in the Wimbledon final.
Matthew Stockman/Getty Images Europe/Getty Images
Williams' defeats, however, are rare, and she will be expected to complete the calendar-year grand slam in September. She's the three-time defending champion at the U.S. Open.
Williams' defeats, however, are rare, and she will be expected to complete the calendar-year grand slam in September. She's the three-time defending champion at the U.S. Open.
Chris Trotman/Getty Images North America/Getty Images for USTA
It's tough, but beating Serena Williams at a major is possible

Read: The tennis stars who believe Serena is beatable

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