Primarily a centre, Clarkson made his representative debut for Natal in 1919 and won a place on the Springboks squad for their 1921 tour of Australasia. He was described by the local New Zealand press as a "cool, reliable (and) solid" player, who possessed "plenty of pace".[2] His tour included two capped appearances, against the All Blacks at Carisbrook and Eden Park. He obtained a third Springboks cap in 1924 against the touring British Lions.[3]