Novak Djokovic of Serbia in action against Marcos Baghdatis of Cyprus during their second round match at the 2015 BNP Paribas Open tennis tournament in Indian Wells, California, USA, 14 March 2015. EPA/PAUL BUCK

Maria Sharapova of Russia in action against Yanina Wickmayer of Belgium during their second round match at the BNP Paribas Open tennis tournament in Indian Wells, California, USA, 14 March 2015. EPA/MICHAEL NELSON

Donald Young Jr. serves to Pablo Carreno Busta at the 2015 BNP Paribas Open, Indian Wells. Photo by Alejandro Gonzalez.

Serena Williams during her match with Monica Niculescu at the BNP Paribas Open. Photo by Alejandro Gonzalez.

Eugenie Bouchard of Canada in action against Lucie Hradecka of Czech Republic in their second round match at the 2015 BNP Paribas Open tennis tournament in Indian Wells, California, USA, 14 March 2015. EPA/PAUL BUCK