Murdoch made his first-class entry in 1875, at the time regarded as the finest wicketkeeper in Australia, and a highly rated right-handed batsman. He played in the second Test match ever played, the 1877 clash against England at the Melbourne Cricket Ground (MCG). Later that year, he qualified as a solicitor and opened up a practice, "Murdoch & Murdoch", with his brother Gilbert, although it was short-lived, going bankrupt in 1877. Murdoch established himself as one of the era's greatest batsmen over the next few years, leading Australia in several Test series against England. In 1881–82 he became the first man other than W. G. Grace to score a first-class triple century when, as captain, he made 321 for New South Wales against Victoria at the SCG. The innings comprised 38 fours, nine threes, 41 twos and 60 singles from all of ten Victorian bowlers. It was this knock which established him in the public reckoning as Australia's finest batsman. So unvanquishable was he that Tom Horan (with whom Murdoch would share many a fine batting stand in the years to come) was reduced to bowling Leg theory, the first known instance of that controversial tactic.