Andrea Petkovic pictured during a press training session organised by her sponsor "Gerolsteiner" at tennis centre 'Rosenhoehe' of the 'Hessian Tennis Association' on July 21, 2014 in Offenbach, Germany.

 Andrea Petkovic during a press training session  at tennis centre 'Rosenhoehe' 

Image by Thomas Lohnes/Getty Images)

 Andrea Petkovic pictured during a press training session  (Photo by Thomas Lohnes/Getty Images)

 

Andrea Petkovic pictured during a press training session in Offenbach, Germany. (Photo by Thomas Lohnes/Getty Images)

 Andrea Petkovic pictured during a press training session organised by her sponsor "Gerolsteiner" at tennis centre 'Rosenhoehe' of the 'Hessian Tennis Association in Offenbach, Germany. (Photo by Thomas Lohnes/Getty Images)

 Andrea Petkovic pictured during a press training session organised by her sponsor "Gerolsteiner" at tennis centre 'Rosenhoehe' , Germany. (Photo by Thomas Lohnes/Getty Images)

Andrea Petkovic pictured during a press training session organised by her sponsor "Gerolsteiner" at tennis centre 'Rosenhoehe' of the 'Hessian Tennis Association' on July 21, 2014 in Offenbach, Germany. (Photo by Thomas Lohnes/Getty Images)

 Tennis pro Andrea Petkovic pictured during a press training session organised by her sponsor "Gerolsteiner" at tennis centre 'Rosenhoehe' of the 'Hessian Tennis Association' on July 21, 2014 in Offenbach, Germany. (Photo by Thomas Lohnes/Getty Images)

 ANDREA PETKOVIC (GER) during practice day of the 2017 US Open on August 26, 2017 at Billie Jean King National Tennis Center, Flushing Meadow, NY.(Photo by Chaz Niell/Icon Sportswire via Getty Images)

 Petkovic pictured during a press training session organised by her sponsor "Gerolsteiner" at tennis centre 'Rosenhoehe' of the 'Hessian Tennis Association' on July 21, 2014 in Offenbach, Germany. (Photo by Thomas Lohnes/Getty Images)

All Images :Getty Images)