Knud Aage Nielsen is a retired male badminton

Badminton

Badminton is a racquet sport played by either two opposing players or two opposing pairs , who take positions on opposite halves of a rectangular court that is divided by a net. Players score points by striking a shuttlecock with their racquet so that it passes over the net and lands in their...

 player from Denmark

Denmark

Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...

.

Nielsen won the All England Open Badminton Championships

All England Open Badminton Championships

The All England Open Badminton Championships, or simply All England, is one of the world's oldest and most prestigious badminton tournaments. Played annually, it developed after the success of world's first badminton tournament held in Guildford in 1898...

, considered the unofficial World Badminton Championships, in men's singles in 1964

1964 All England Open Badminton Championships

The 1964 All England Open was the 54th edition of the All England Open Badminton Championships. It was held in 1964, in Wembley, London.-Final results:...

. He played Thomas Cup

Thomas Cup

The Thomas Cup, sometimes called the World Men's Team Championships, is an international badminton competition among teams representing member nations of the Badminton World Federation , the sport's global governing body...

 (men's international team competition) singles for Denmark

Denmark national badminton team

The Denmark national badminton team is a badminton team located in Denmark and represents the nation of Denmark in international badminton team competitions...

 in the '60-'61

1961 Thomas Cup

The Thomas Cup competition is an international team tournament for supremacy in men's badminton . Beginning in 1948-1949 it was held every three years until 1982 and thereafter every two years...

 and '63-'64
campaigns

1964 Thomas Cup

The Thomas Cup competition is an international team tournament for supremacy in men's badminton . Beginning in 1948-1949 it was held every three years until 1982 and thereafter it has been held every two years...

, scoring Denmark's only singles victory in its surprising '64 Challenge Round loss to Indonesia.