2016 Rio Olympics - Tennis - Final - Men's Singles Gold Medal Match - Olympic Tennis Centre - Rio de Janeiro, Brazil - 14/08/2016. Juan Martin Del Potro (ARG) of Argentina in action against Andy Murray (GBR) of Britain. REUTERS/Marcos Brindicci

2016 Rio Olympics - Tennis - Final - Men's Singles Gold Medal Match - Olympic Tennis Centre - Rio de Janeiro, Brazil - 14/08/2016. Andy Murray (GBR) of Britain celebrates after winning his match against Juan Martin Del Potro (ARG) of Argentina. REUTERS/Toby Melville

2016 Rio Olympics - Tennis - Final - Men's Singles Gold Medal Match - Olympic Tennis Centre - Rio de Janeiro, Brazil - 14/08/2016. Andy Murray (GBR) of Britain reacts during his match against Juan Martin Del Potro (ARG) of Argentina. REUTERS/Marcos Brindicci

2016 Rio Olympics - Tennis - Final - Men's Singles Gold Medal Match - Olympic Tennis Centre - Rio de Janeiro, Brazil - 14/08/2016. Juan Martin Del Potro (ARG) of Argentina reacts during match against Andy Murray (GBR) of Britain. REUTERS/Marcos Brindicci

2016 Rio Olympics - Tennis - Final - Men's Singles Gold Medal Match - Olympic Tennis Centre - Rio de Janeiro, Brazil - 14/08/2016. Andy Murray (GBR) of Britain in action against Juan Martin Del Potro (ARG) of Argentina. REUTERS/Toby Melville

2016 Rio Olympics - Tennis - Final - Men's Singles Gold Medal Match - Olympic Tennis Centre - Rio de Janeiro, Brazil - 14/08/2016. Juan Martin Del Potro (ARG) of Argentina reacts during match against Andy Murray (GBR) of Britain. REUTERS/Kevin Lamarque

2016 Rio Olympics - Cycling Track - Preliminary - Men's Omnium 4km Individual Pursuit - Rio Olympic Velodrome - Rio de Janeiro, Brazil - 14/08/2016. Mark Cavendish (GBR) of Britain. REUTERS/Eric Gaillard

2016 Rio Olympics - Badminton - Men's Singles Group Play - Riocentro - Pavilion 4 - Rio de Janeiro, Brazil - 14/08/2016. Zi Liang Derek Wong (SIN) of Singapore plays against Chong Wei Lee (MAS) of Malaysia. REUTERS/Jeremy Lee