Central Coast Mariners In October 2019, Miller was awarded a TAG Foundation scholarship with
Central Coast Mariners, following a strong pre-season. Three months later, in January 2020, he signed a two-year contract, upgrading him to a professional senior contract.
Hibernian In June 2022 Miller signed a three-year contract for Scottish side
Hibernian, effective from 1 July. He had been due to join Australian side
Macarthur FC, having signed a pre-contract deal with them before the end of his contract at Central Coast Mariners, but then signed for Hibernian instead, netting Macarthur FC an undisclosed transfer fee. In April 2025, Hibs activated a one-year extension to Miller's contract.
Blackburn Rovers In August 2025, Miller signed a 3-year deal with the option of a further 12 months at
Blackburn Rovers. On 21 November 2025, Miller scored his first goal for the club with a header in a 2–1 away win over
Preston North End. On 11 January 2026, Miller was named captain in a 0–0 draw with
Hull City in the
FA Cup following the absence of
Todd Cantwell from the matchday squad. On 14 February, Miller came on as a half-time substitute in a 3–1 win over
Queens Park Rangers but was stretchered off after 9 minutes. Blackburn later confirmed that he had suffered a complete rupture of his
Achilles tendon, ruling him out for an estimated nine months and excluding him from participating in the
2026 FIFA World Cup with Australia. ==International career==