*Club domestic league appearances and goals, correct as of 10:20, 28 October 2024 (UTC) ‡ National team caps and goals, correct as of 17:42, 18 March 2021 (UTC)
Scully joined West Ham United as a youth player in 2011. On 23 May 2016, West Ham announced Scully had signed his first professional contract with the club. During Scully's time at West Ham, he appeared as a triallist for Norwich City and Nottingham Forest.[3][4]
Lincoln City
On 3 February 2020, after 37 appearances for West Ham's under-23's, Scully signed for League One club Lincoln City.[5] On 15 February 2020, on his first start for Lincoln, Scully scored his maiden goal for the club in a 4–3 loss against Accrington Stanley.[6] He would sign a new contract on 25 February 2021, keeping him at the club until the summer of 2023.[7] His form during September 2021, would see him nominated for the EFL Player of the Month for League One.[8]
Wigan Athletic
On 1 September 2022, Scully signed for Wigan Athletic for an undisclosed fee.[9]
Portsmouth
On 16 June 2023 Scully signed for EFL League One side Portsmouth.[10] His playing time was limited with the club throughout 2023–24 as the side went on to win the league title and promotion to the EFL Championship.
Colchester United (Loan)
On 30 August 2024, Deadline Day of the 2024 Summer transfer window Scully joined EFL League Two side Colchester United.[11]
International career
Scully initially represented Ireland's under-15's,[12] before switching allegiances to play for England's under-16 side.[13] Scully later returned to the Irish set-up, captaining the under-17's.[4] He also has represented Ireland at u21 level.