Rafael Nadal of Spain returns the ball to Kei Nishikori of Japan during their men’s singles bronze medal match of the Rio 2016 Olympic Games Tennis events at the Olympic Tennis Centre in the Olympic Park in Rio de Janeiro, Brazil, 14 August 2016. EPA/MICHAEL REYNOLDS

Kei Nishikori of Japan in action against Rafael Nadal of Spain during their tennis match for the Bronze medal at Rio 2016 Olympic Games at the Olympic Tennis Center in Rio de Janeiro, Brazil, 14 August 2016. EPA/MICHAEL REYNOLDS

Kei Nishikori of Japan in action against Rafael Nadal of Spain during their tennis match for the Bronze medal at Rio 2016 Olympic Games at the Olympic Tennis Center in Rio de Janeiro, Brazil, 14 August 2016. EPA/MICHAEL REYNOLDS

Rafael Nadal of Spain celebrates a point against Kei Nishikori of Japan during their tennis match for the Bronze medal at Rio 2016 Olympic Games at the Olympic Tennis Center in Rio de Janeiro, Brazil, 14 August 2016. EPA/LEONARDO MUNOZ

Rafael Nadal of Spain leaves the field after losing against Kei Nishikori of Japan during their tennis match for the Bronze medal at Rio 2016 Olympic Games at the Olympic Tennis Center in Rio de Janeiro, Brazil, 14 August 2016. EPA/LEONARDO MUNOZ