Todd Murphy started playing cricket at a young age, honing his skills at the Normanhurst-Warrawee Cricket Club in the local Sydney Shires competition. Murphy represented the NSW Metro and NSW Schools teams as a junior. A right-arm off-spinner known for his accuracy and ability to extract turn, Murphy made his first-class debut for New South Wales in 2020 at age 19 in a Sheffield Shield match against Tasmania. He picked up three wickets in his debut innings.

In the 2020-21 season, Murphy established himself as a regular in the NSW side across all formats. He ended up as the team's leading wicket-taker in that Sheffield Shield season with 23 dismissals at an impressive average of 26.43.

Murphy's breakout season was 2021-22 when he was the highest wicket-taker for NSW in both the Sheffield Shield (32 wickets) and the One-Day Cup (17 wickets). His performances with the red and white ball earned him a well-deserved call-up to Australia's squad for the 2022 Pakistan tour.

In March 2022 at the age of  21, Todd Murphy made his Test debut for Australia in the opening match against Pakistan in Rawalpindi. He picked up seven wickets across the two innings, forming a handy spin partnership with veteran Nathan Lyon.

That debut performance was enough to convince Australia's selectors to retain Murphy for the India tour later in 2022-23. He made his home Test debut against the West Indies in Perth in December 2022, claiming another five-wicket haul.

Against India in the 2023 Border-Gavaskar Trophy, he was Australia's second-highest wicket-taker with 14 dismissals at an average of 25.5,

So far in his international career spanning 6 Tests, the 22-year-old Murphy has already accounted for 35 wickets at an average under 30. He has been particularly effective in Asia, taking 24 wickets from just 3 Tests in Pakistan and India.

At the domestic level, Todd Murphy has played 20 first-class matches for New South Wales so far, capturing 95 wickets at an outstanding average of 24.28.