Career
His usual position was at number eight. Muller made his international debut for the Springboks on 16 July 1949, in the starting line-up in the first a four matches against the touring All Blacks. In 1951 Muller skippered South Africa at Murrayfield in Edinburgh, which saw the Springboks run away 44–0 winners, with Muller scoring one try.
After defeating Scotland, the Springboks had the tough task of playing the other three home nations, as well as France on the rest of the tour.
The Springboks made it two from two at Lansdowne Road, defeating Ireland 17–5. Muller guided the team to a closer victory in the subsequent match against Wales in Cardiff, which saw the Springboks keep the clean winning record on tour 3–0, winning the game 6–3, a South African drop-goal proving the difference between the two sides.
The tour had now entered early January, and the next assignment for the Springboks was to face the English at Twickenham. The Springboks came a step closer to getting a grand slam, defeating England 8–3, with Muller adding five of South Africa"s nine points, with a conversion and penalty goal.
The Springboks ran in six tries to defeat France 25–3, Muller scoring one of the tries, as well as adding a conversion, and thus, South Africa completing a grand slam tour of Europe.
Muller captained the side against the Wallabies for a four test series in South Africa in 1953. The Wallabies hit back in Cape Town, taking the second test 18–14. Muller would go onto coach the Springboks in 1965.
In 2001, he was inducted into the International Rugby Hall of Fame.