He played as a flanker. Kruger played for the South Africa national rugby union team between 1993 and 1999. In 1995, he played in the Rugby World Cup.
During this tournament, he made 5 starts, and scored 1 try, in the controversial semi-final against the France national rugby union team
He also played in the 1999 World Cup. In 1995 Ruben Kruger was named South African Rugby Football Union"s player of the year.
At the end of his rugby career, he became a camera salesman. He owned a Minolta franchise in Pretoria.
He was portrayed in Invictus, a film about Nelson Mandela and the 1995 Springboks, by Grant Roberts.
Death Kruger died in Pretoria on 27 January 2010 after battling brain cancer for 10 years. He was two months short of his 40th birthday. Province Free State Cheetahs Northern Transvaal (Super 12) until 1996 Bulls (Super 14) since 1996 Springboks 36 caps 7 tries (35 points) Caps by season: 2 in 1993, 2 in 1994, 9 in 1995, 13 in 1996, 6 in 1997, 4 in 1999.
World Cups 1995: world champions, 5 selections (Wallabies, Romania, Samoa, France, All Blacks).