In September 2021, Bos signed his first professional contract with Melbourne City on a three-year deal.[6] Bos made his first-team debut for City on 27 November 2021 as a substitute in a 2–2 draw to Adelaide United at Coopers Stadium.[7] He scored his first professional goal on 6 April 2022, opening the score in a 4–0 win over Sydney FC.[8][9] Bos was a part of Melbourne City's campaign in the 2021–22 season and 2022–23 season, where he claimed two A-League Men’s Premierships in 50 appearances, including three goals and six assists, for the club.[10]
KVC Westerlo
On 16 May 2023, it was announced that Bos would join Belgian Pro League side Westerlo at the end of the 2022–23 season, signing a four-year contract with his new club.[11][12][13] While the transfer fee was kept undisclosed, it was reported that the deal broke the previous records both for Melbourne City (originally set by Aaron Mooy in 2016) and for any A-League club (which had belonged to Zeljko Kalac since 1995).[10][12][14] Bos' record as the most expensive transfer domestic player in Australia stood until June 2023, when former teammate Marco Tilio was sold to Celtic from City for a record undisclosed fee.[15]
After injuring his hamstring playing domestically, Bos missed two matches in Australia's 2026 FIFA World Cup qualification, sitting on the sidelines for matches against Bahrain and Japan in September of 2024. He returned for a 3–1 victory over China in October.[18]
International goals
Scores and results list Australia's goal tally first.
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