Victoria Azarenka of Belarus in action against Angelique Kerber of Germany during their semifinal round match at the Miami Open tennis tournament on Key Biscayne, Miami, Florida, USA, 31 March 2016. EPA/ERIK S. LESSER

A tennis fan watches as Svetlana Kuznetsova of Russia faces Timea Bacsinszky of Switzerland during their semi final match at the Miami Open tennis tournament on Key Biscayne, Miami, Florida, USA, 31 March 2016. EPA/ERIK S. LESSER

Timea Bacsinszky of Switzerland in action against Svetlana Kuznetsova of Russia during a semifinal round match at the Miami Open tennis tournament on Key Biscayne, Miami, Florida, USA, 31 March 2016. EPA/ERIK S. LESSER

Angelique Kerber of Germany in action during her semifinal match against Victoria Azarenka of Belarus at the Miami Open tennis tournament on Key Biscayne, Miami, Florida, USA, 31 March 2016. EPA/RHONA WISE

Svetlana Kuznetsova of Russia reacts after defeating Timea Bacsinszky of Switzerland during their semi final match at the Miami Open tennis tournament on Key Biscayne, Miami, Florida, USA, 31 March 2016. EPA/ERIK S. LESSER