[5] McNally's first involvement in a first-team squad was on 8 August 2017, when he was named on the bench for a Leinster Senior Cup game against Firhouse Clover, remaining an unused substitute.
[6] On 8 February 2019, it was announced that McNally had signed a two-year professional contract with St Patrick's Athletic, while he would be loaned to Drogheda United for the 2019 League of Ireland First Division season.
[8] His competitive debut in senior football came on the opening night of the League of Ireland First Division season, as his side beat Cobh Ramblers 4–0 at United Park.
[25][26] The move failed to materialise, however, and he stayed at St Patrick's Athletic and scored his first goal for the club in a 3–2 loss to Finn Harps on 8 October 2020 with a header from a corner.
[30][31][32][33][34] He spent his first few months at the club undergoing a 'mini pre-season' to get fit following a hip injury,[35] first making the first-team matchday squad on 2 April 2021 when he was an unused substitute away to Sunderland.
[44] On 26 January 2023 with game time at Turf Moor proving difficult to come by, McNally signed for Championship club Coventry City on loan until the end of the season.
[45] McNally made 22 appearances in all competitions for the club, including the full 120 minutes of the 2023 EFL Championship play-off final as his side missed out on promotion to the Premier League by losing on penalties to Luton Town at Wembley Stadium.
[46] Following Burnley's promotion to the Premier League, it was announced on 2 August 2023 that McNally had signed for EFL Championship club Stoke City on a season-long loan deal.