Maria Sharapova of Russia serves to Bethanie Mattek-Sands of the United States during their women's singles match at the Australian Open 2014 tennis tournament in Melbourne January 14, 2014. REUTERS/David Gray (AUSTRALIA - Tags: SPORT TENNIS)

Maria Sharapova of Russia reacts during her women's semi-final match against Eugenie Bouchard of Canada at the French Open tennis tournament at the Roland Garros stadium in Paris June 5, 2014. REUTERS/Stephane Mahe (FRANCE - Tags: SPORT TENNIS TPX IMAGES OF THE DAY)

Tennis player Maria Sharapova of Russia plays with a fan during an
event promoting tennis in Hong Kong, December 29, 2002. Sharapova, 15,
the latest young player to be saddled with the title "the next Anna
Kournikova", will participate in the Hong Kong Ladies Challenge which
will begin on January 1, 2003. REUTERS/Kin Cheung

BY,DL 

Russia's Maria Sharapova celebrates her win against compatriot Elena
Bovina in their second round match at the Wimbledon Tennis
Championships in London, June 26, 2003. Sharapova won the match 6-3
6-1. REUTERS/Alessandro Bianchi

AB/ASA/JV 

Thirteenth seed Maria Sharapova (L) of Russia and Serena Williams of the U.S. hold their respective trophies after their women's final match at the Wimbledon Tennis Championships in London, July 3, 2004. Seventeen-year-old Sharapova won the match, which was her first Wimbledon and Grand Slam singles title, 6-1 6-4. REUTERS/Kevin Lamarque MD/WS 

Maria Sharapova of Russia poses with her trophy in the dressing room after winning the women's singles final match against Sara Errani of Italy during the French Open tennis tournament at the Roland Garros stadium in Paris June 9, 2012. REUTERS/Sindy Thomas/FFT/Pool (FRANCE - Tags: SPORT TENNIS) 

Maria Sharapova of Russia hits the ball to Belarussia's Darya Kustova during their second round match of the WTA Warsaw Open Tennis tournament at Legia tennis courts in Warsaw May 20, 2009. REUTERS/Adam Nurkiewicz (POLAND SPORT TENNIS) 

Maria Sharapova of Russia poses with her trophy for photographers near the Eiffel Tower in Paris a day after winning the women's singles final match during the French Open tennis tournament at the Roland Garros stadium in Paris June 8, 2014. REUTERS/Gonzalo Fuentes (FRANCE - Tags: SPORT TENNIS TPX IMAGES OF THE DAY MEDIA)

Maria Sharapova of Russia returns the ball to Christina McHale of the U.S. during their match at the Madrid Open tennis tournament May 6, 2014. REUTER/Andrea Comas (SPAIN - Tags: SPORT TENNIS) 

Maria Sharapova of Russia reacts during her match against Coco Vandeweghe of the U.S.A. at the Wimbledon Tennis Championships in London, July 7, 2015. REUTERS/Stefan Wermuth TPX IMAGES OF THE DAY

Maria Sharapova of Russia wears shoes with her name monogrammed on the back during the final of the Sony Ericsson Open tennis tournament in Key Biscayne, Florida, April 2, 2011. REUTERS/Hans Deryk (UNITED STATES - Tags: SPORT TENNIS FASHION) 

Maria Sharapova of Russia poses next to a Boxster Porsche car as she visits the Taste Festival at the Grand Palais in Paris, France, May 21, 2015. Sharapova will compete in the French Open tennis tournament which starts on May 19th at the Roland Garros stadium. REUTERS/Charles Platiau 

Tennis star Maria Sharapova poses on the red carpet before launching her new TAG Heuer AQUARACER Steel & 18K Gold watch with diamonds and her new charity "The Maria Sharapova Foundation" at Bloomingdales in New York, August 22, 2006. REUTERS/Shannon Stapleton (United States) 

Maria Sharapova of Russia holds a bag of her gummy candy line "Sugarpova" during a media availability at the BNP Paribas Open WTA tennis tournament in Indian Wells, California, March 6, 2013. REUTERS/Danny Moloshok (UNITED STATES - Tags: SPORT TENNIS BUSINESS) 

Russian tennis star Maria Sharapova walks past Japanese models holding Samantha Thavasa handbags, which she designed, during a fashion show in Tokyo December 23, 2005. The Maria Sharapova Japan Tour 2005 is the first leg of a tentatively scheduled world tour which will include Russia, Hong Kong and Singapore in the coming months. The 18-year-old Russian is promoting her own brand of perfume and her line of watches in addition to taking part in fashion shows, tennis clinics for children and doubles matches in Osaka, Nagoya and Tokyo. REUTERS/Yuriko Nakao 

(L-R) Photographer Mario Testino, U.S. Vogue editor Anna Wintour and tennis woman Russia's Maria Sharapova attend the Spring/Summer 2016 women's ready-to-wear collection for fashion house Chanel at the Grand Palais which is transformed into a Chanel airport during the Fashion Week in Paris, France, October 6, 2015. REUTERS/Charles Platiau 

Maria Sharapova of Russia reacts after winning a point against Maria Elena Camerin of Italy during their match at the Nasdaq-100 Open tennis tournament in Key Biscayne, Florida March 26, 2006. REUTERS/Carlos Barria 

Russia's Maria Sharapova serves during her third round match against Lauren Davis of the U.S. at the Australian Open tennis tournament at Melbourne Park, Australia, January 22, 2016. REUTERS/Thomas Peter TPX IMAGES OF THE DAY 

Maria Sharapova of Russia poses for photographers as she holds her trophy after winning the final match over Carla Suarez Navarro of Spain at the Rome Open tennis tournament in Rome, Italy, May 17, 2015. REUTERS/Stefano Rellandini TPX IMAGES OF THE DAY

Maria Sharapova of Russia signs autographs after defeating Eugenie Bouchard of Canada in their women's singles quarter-final match at the Australian Open 2015 tennis tournament in Melbourne January 27, 2015. REUTERS/Thomas Peter (AUSTRALIA - Tags: SPORT TENNIS TPX IMAGES OF THE DAY)

Maria Sharapova of Russia stands in the shade during her during their women's singles match against Dominika Cibulkova of Slovakia at the Australian Open 2014 tennis tournament in Melbourne January 20, 2014. REUTERS/David Gray (AUSTRALIA - Tags: SPORT TENNIS TPX IMAGES OF THE DAY)

Vogue editor Anna Wintour (C) sits with tennis player Maria Sharapova (R) and singer Alicia Keys before a presentation of the Jason Wu Spring/Summer 2014 collection during New York Fashion Week September 6, 2013. REUTERS/Lucas Jackson (UNITED STATES - Tags: FASHION MEDIA SPORT TENNIS ENTERTAINMENT TPX IMAGES OF THE DAY) 

Maria Sharapova of Russia slips during her women's singles tennis match against Michelle Larcher De Brito of Portugal at the Wimbledon Tennis Championships, in London June 26, 2013. REUTERS/Stefan Wermuth (BRITAIN - Tags: SPORT TENNIS TPX IMAGES OF THE DAY)

Tennis player Maria Sharapova poses for photographers as she promotes her "Sugarpova" confectionary brand in London June 20, 2013. REUTERS/Neil Hall (BRITAIN - Tags: BUSINESS FOOD SPORT TENNIS) 

Russia's Maria Sharapova watches Bulgaria's Grigor Dimitrov play Israel's Dudi Sela in their men's singles tennis match at the Queen's Club Championships in west London June 10, 2013. REUTERS/Toby Melville (BRITAIN - Tags: SPORT TENNIS) 

Maria Sharapova of Russia poses with her trophy and the Russian flag after defeating Caroline Wozniacki of Denmark in the women's singles final match at the BNP Paribas Open WTA tennis tournament in Indian Wells, California March 17, 2013. REUTERS/Danny Moloshok (UNITED STATES - Tags: SPORT TENNIS) 

Russian tennis player Maria Sharapova poses at the premiere of "10,000 B.C." at the Grauman's Chinese theatre in Hollywood, California March 5, 2008. The movie opens in the U.S. on March 7. REUTERS/Mario Anzuoni (UNITED STATES) 

Russia's Maria Sharapova sits on a motorcycle after defeating compatriot Vera Zvonareva in the final of the Qatar Open tennis tournament in Doha February 24,2008. REUTERS/Fadi Al-Assaad (QATAR) 

Tennis player Maria Sharapova (L) of Russia and NBA basketball player LeBron James of the U.S. pose for photographer Patrick Demarchelier (not pictured) for a United Nations Development Programme campaign in New York September 25, 2007. REUTERS/Joshua Lott (UNITED STATES) 

Maria Sharapova of Russia reacts during her match against Casey Dellacqua of Australia at the U.S. Open tennis tournament in Flushing Meadows, New York, August 30, 2007. REUTERS/Jeff Zelevansky (UNITED STATES) 

Russia's Maria Sharapova leaves a Pan Pacific Open Tennis Tournament news conference in Tokyo January 29, 2007. REUTERS/Toru Hanai (JAPAN) 

Russia's Maria Sharapova holds the women's U.S. Open trophy at the U.S. Open tennis tournament in New York, September 9, 2006. Sharapova defeated Belgium's Justine Henin-Hardenne 6-4 6-4. REUTERS/Mike Segar (UNITED STATES) 

Russia's Maria Sharapova sits in the shade of an umbrella during a break in her match against Italy's Flavia Pennetta at the Wimbledon tennis championships in London July 3, 2006. REUTERS/Alessia Pierdomenico (BRITAIN) 

Russia's tennis star Maria Sharapova (C) looks at two male models, who will act as ball-boys in the WTA Tour Championships in November during a selection process along with a celebrity panel, in a central hotel in Madrid May 11, 2006. REUTERS/Andrea Comas 

PICTURES OF THE YEAR 2004 - Thirteenth seed Maria Sharapova of Russia kisses the trophy after defeating top seed Serena Williams of the U.S. in their final match at the Wimbledon Tennis Championships in London, July 3, 2004. was her first Wimbledon and Grand Slam singles title, 6-1 6-4. REUTERS/Kevin Lamarque GMH/SV 

RUSSIA'S SHARAPOVA LEAVES CENTRE COURT IN RAIN DELAY IN HER SEMI-FINAL AGAINST DAVENPORT OF THE U.S. AT WIMBLEDON. Thirteenth seed Russia's Maria Sharapova (C) walks off Centre Court as ground staff pull the covers across during the second rain delay of her semi-final match against fifth seed Lindsay Davenport of the U.S. at the Wimbledon Tennis Championships in London, July 1, 2004. REUTERS/Kevin Lamarque Pictures of the Year 2004 

Russia's Maria Sharapova celebrates after winning her fourth round match against Switzerland's Belinda Bencic at the Australian Open tennis tournament at Melbourne Park, Australia, January 24, 2016. REUTERS/Thomas Peter TPX IMAGES OF THE DAY