From 1970 to 1974, he played 11 matches as fullback for the Springboks, the South African national rugby union team.
[4] McCallum's first test for the Springboks was in 1970 against the New Zealand at Loftus Versfeld in Pretoria.
He also played in the test series against France and Australia in 1971 and against the British Lions in 1974.
Both he and his brother, Roy, were in the Springbok team for the first Test against the British Lions at Newlands in 1974.
McCallum played a further six tour matches, scoring seventy-two points for the Springboks.