Career
As an umpire he officiated in first-class and Test cricket matches. During the late 1960s he played for Transvaal as a wicket-keeper in South African domestic cricket. He later became an umpire, culminating with him becoming a Test cricket umpire.
Between 1992 and 2000, he stood in 26 Test matches and 61 One Day Internationals (ODIs).
In a match between South Africa and India in 1992, Mitchley made history by making the first referral to a third umpire in Test cricket history. Sachin Tendulkar was out after Mitchley referred a run out decision.
He later became an Interstate Commerce Commission match referee, officiating on four ODIs, all in 2007.