McMillan was a right arm medium-pace bowler and right-handed batsman. He was also a leading slip fielder, and holds the highest percentage of catches per Test for an outfielder in South Africa Test cricket history.
McMillan made his Test debut in November 1992, against India at Durban, in South Africa’s first home Test match in over 20 years. He was to become a key member of the South African team post their re-admittance to world cricket in 1991.
In domestic cricket, he represented Transvaal for four seasons from 1984-85 to 1988-89, and Western Province from 1989-90 until his retirement in the 1999-00 season . He also spent a season with Warwickshire in 1986.
McMillan has also been a professional teacher in a Durban university. He currently heads an office automation firm in Cape Town.