Tennis - WTA - Madrid Open - Roberta Vinci of Italy v Simona Halep of Romania - Madrid, Spain - 9/5/17 - Vinci reacts. REUTERS/Susana Vera 

Tennis - WTA - Madrid Open - Roberta Vinci of Italy v Simona Halep of Romania - Madrid, Spain - 9/5/17 - Halep serves the ball. REUTERS/Susana Vera 

Tennis - WTA - Madrid Open - Roberta Vinci of Italy v Simona Halep of Romania - Madrid, Spain - 9/5/17 - Halep returns the ball. REUTERS/Susana Vera 

Tennis - WTA - Madrid Open - Roberta Vinci of Italy v Simona Halep of Romania - Madrid, Spain - 9/5/17 - Halep serves the ball. REUTERS/Susana Vera 

Tennis - WTA - Madrid Open - Roberta Vinci of Italy v Simona Halep of Romania - Madrid, Spain - 9/5/17 - Halep celebrates at the end of match. REUTERS/Susana Vera 

Tennis - WTA - Madrid Open - Roberta Vinci of Italy v Simona Halep of Romania - Madrid, Spain - 9/5/17 - Halep returns the ball. REUTERS/Susana Vera 

Tennis - WTA - Madrid Open - Roberta Vinci of Italy v Simona Halep of Romania - Madrid, Spain - 9/5/17 - Halep celebrates at the end of match. REUTERS/Susana Vera 

Tennis - WTA - Madrid Open - Roberta Vinci of Italy v Simona Halep of Romania - Madrid, Spain - 9/5/17 - Halep returns the ball. REUTERS/Susana Vera 

Tennis - WTA - Madrid Open - Roberta Vinci of Italy v Simona Halep of Romania - Madrid, Spain - 9/5/17 - Vinci returns a shot. REUTERS/Paul Hanna 

Tennis - WTA - Madrid Open - Roberta Vinci of Italy v Simona Halep of Romania - Madrid, Spain - 9/5/17 - Halep returns the ball. REUTERS/Paul Hanna 

Tennis - WTA - Madrid Open - Roberta Vinci of Italy v Simona Halep of Romania - Madrid, Spain - 9/5/17 - Vinci returns a shot. REUTERS/Paul Hanna 

Tennis - WTA - Madrid Open - Roberta Vinci of Italy v Simona Halep of Romania - Madrid, Spain - 9/5/17 - Vinci serves. REUTERS/Paul Hanna 

Tennis - WTA - Madrid Open - Roberta Vinci of Italy v Simona Halep of Romania - Madrid, Spain - 9/5/17 - Halep returns the ball. REUTERS/Paul Hanna 

Tennis - WTA - Madrid Open - Roberta Vinci of Italy v Simona Halep of Romania - Madrid, Spain - 9/5/17 - Halep serves the ball. REUTERS/Paul Hanna 

Tennis - WTA - Madrid Open - Roberta Vinci of Italy v Simona Halep of Romania - Madrid, Spain - 9/5/17 - Halep serves the ball. REUTERS/Paul Hanna 

Tennis - WTA Stuttgart Tennis Grand Prix - Maria Sharapova of Russia v Roberta Vinci of Italy - Stuttgart, Germany - 26/4/17. Maria Sharapova of Russia in action. REUTERS/Ralph Orlowski 

Tennis - WTA Stuttgart Tennis Grand Prix - Maria Sharapova of Russia v Roberta Vinci of Italy - Stuttgart, Germany - 26/4/17. Maria Sharapova of Russia in action. REUTERS/Ralph Orlowski 

Tennis - WTA Stuttgart Tennis Grand Prix - Maria Sharapova of Russia v Roberta Vinci of Italy - Stuttgart, Germany - 26/4/17. Maria Sharapova of Russia in action. REUTERS/Ralph Orlowski 

Tennis - WTA Stuttgart Tennis Grand Prix - Maria Sharapova of Russia v Roberta Vinci of Italy - Stuttgart, Germany - 26/4/17. Maria Sharapova of Russia in action. REUTERS/Ralph Orlowski 

Tennis - WTA Stuttgart Tennis Grand Prix - Maria Sharapova of Russia v Roberta Vinci of Italy - Stuttgart, Germany - 26/4/17. Maria Sharapova of Russia in action. REUTERS/Ralph Orlowski 

Tennis - WTA Stuttgart Tennis Grand Prix - Maria Sharapova of Russia v Roberta Vinci of Italy - Stuttgart, Germany - 26/4/17. Maria Sharapova of Russia in action. REUTERS/Ralph Orlowski 

Tennis - WTA Stuttgart Tennis Grand Prix - Maria Sharapova of Russia v Roberta Vinci of Italy - Stuttgart, Germany - 26/4/17. Maria Sharapova of Russia in action. REUTERS/Ralph Orlowski 

Tennis - WTA Stuttgart Tennis Grand Prix - Maria Sharapova of Russia v Roberta Vinci of Italy - Stuttgart, Germany - 26/4/17. Maria Sharapova of Russia in action. REUTERS/Ralph Orlowski 

Tennis - WTA Stuttgart Tennis Grand Prix - Maria Sharapova of Russia v Roberta Vinci of Italy - Stuttgart, Germany - 26/4/17. Maria Sharapova of Russia in action. REUTERS/Ralph Orlowski 

Tennis - WTA Stuttgart Tennis Grand Prix - Maria Sharapova of Russia v Roberta Vinci of Italy - Stuttgart, Germany - 26/4/17. Maria Sharapova of Russia in action. REUTERS/Ralph Orlowski 

Tennis - WTA Stuttgart Tennis Grand Prix - Maria Sharapova of Russia v Roberta Vinci of Italy - Stuttgart, Germany - 26/4/17. Maria Sharapova of Russia in action. REUTERS/Ralph Orlowski 

Tennis - WTA Stuttgart Tennis Grand Prix - Maria Sharapova of Russia v Roberta Vinci of Italy - Stuttgart, Germany - 26/4/17. Maria Sharapova of Russia in action. REUTERS/Ralph Orlowski 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. lies on the court after winning the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. reacts after winning the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. reacts after winning the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. leaves after signing autographs following her win during the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. signs autographs after winning the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed TPX IMAGES OF THE DAY 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Italy's Roberta Vinci leaves the court after losing to Coco Vandeweghe of the U.S. in their Women's singles first round match. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. shakes hands with Italy's Roberta Vinci after winning their Women's singles first round match. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. falls onto the court after winning the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. falls onto the court after winning the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. lies on the court after winning the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed TPX IMAGES OF THE DAY 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. takes a drink during the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. takes off a towel filled with ice after being assisted by a medical staff during the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Italy's Roberta Vinci hits a shot during the Women's singles first round match against Coco Vandeweghe of the U.S. . REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Italy's Roberta Vinci reacts during the Women's singles first round match against Coco Vandeweghe of the U.S. . REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Italy's Roberta Vinci reacts during the Women's singles first round match against Coco Vandeweghe of the U.S. . REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Italy's Roberta Vinci hits a shot during the Women's singles first round match against Coco Vandeweghe of the U.S. . REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. hits a shot during the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. is assisted by a medical staff as she rests during the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. is assisted by a medic as she rests on the court during the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. rests on the court during the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. casts a shadow during the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. hits a shot during the Women's singles first round match against Italy's Roberta Vinci. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Coco Vandeweghe of the U.S. serves during the Women's singles first round match against Italy's Roberta Vinci.REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 16/1/17 Italy's Roberta Vinci hits a shot during the Women's singles first round match against Coco Vandeweghe of the U.S. .REUTERS/Jason Reed 

Musician Drake applauds as his image is displayed on the TV monitors during the Serena Williams, Roberta Vinci match at the U.S. Open Championships tennis tournament in New York, September 11, 2015. REUTERS/Carlo Allegri/File Photo 

Britain Tennis - Wimbledon - All England Lawn Tennis & Croquet Club, Wimbledon, England - 3/7/16 USA's Coco Vandeweghe shakes hands with Italy's Roberta Vinci after winning their match REUTERS/Tony O'Brien 

Britain Tennis - Wimbledon - All England Lawn Tennis & Croquet Club, Wimbledon, England - 3/7/16 USA's Coco Vandeweghe celebrates winning her match against Italy's Roberta Vinci REUTERS/Tony O'Brien 

Britain Tennis - Wimbledon - All England Lawn Tennis & Croquet Club, Wimbledon, England - 3/7/16 Italy's Roberta Vinci in action against USA's Coco Vandeweghe REUTERS/Tony O'Brien 

Britain Tennis - Wimbledon - All England Lawn Tennis & Croquet Club, Wimbledon, England - 3/7/16 USA's Coco Vandeweghe during her match against Italy's Roberta Vinci REUTERS/Tony O'Brien 

Britain Tennis - Wimbledon - All England Lawn Tennis & Croquet Club, Wimbledon, England - 3/7/16 USA's Coco Vandeweghe in action against Italy's Roberta Vinci REUTERS/Tony O'Brien 

Britain Tennis - Wimbledon - All England Lawn Tennis & Croquet Club, Wimbledon, England - 3/7/16 USA's Coco Vandeweghe in action against Italy's Roberta Vinci REUTERS/Tony O'Brien 

Britain Tennis - Wimbledon - All England Lawn Tennis & Croquet Club, Wimbledon, England - 3/7/16 Italy's Roberta Vinci in action against USA's Coco Vandeweghe REUTERS/Tony O'Brien 

Britain Tennis - Wimbledon - All England Lawn Tennis & Croquet Club, Wimbledon, England - 3/7/16 USA's Coco Vandeweghe in action against Italy's Roberta Vinci REUTERS/Tony O'Brien