Cieran joined Town in July 2023, signing from European champions Manchester City for an undisclosed fee.

His first season at the Club saw him play a part as the Blues were promoted to the Premier League, making two appearances in cup competitions and helping the Blues to a penalty shootout victory over Reading along the way. With Christian Walton injured at the beginning of the campaign, Cieran backed up starting goalkeeper Vaclav Hladky and was a vital member of the goalkeeping unit throughout the season.

During his time at City, Cieran was named on the bench for games in both the Premier League and Champions League, while also spending time on loan with Rochdale in League Two during the 2022/23 season.

He signed a three-year deal at Town, joining up with the Blues' senior goalkeepers ahead of a pre-season training camp in Austria.