[6] Despite his continued difficulty in breaking into the starting XI, with Joel Castro Pereira the preferred goalkeeper, O'Hara signed a professional deal with the Reds in the summer of 2014.

After a one-month loan with Conference North title-contenders AFC Fylde,[8] O'Hara was given his first opportunity for United in the final game of the Under-21 Premier League season.

[9] O'Hara opted for senior football once more during the 2015–16 season, and completed a deadline day move to League Two club Morecambe on a one-month loan in the summer.

[10] He later faced a one-month loan spell with National League North club Stockport County in November,[9] before returning to Morecambe for the remainder of the season on 12 January.

[11] Having failed to make a competitive appearance in his first spell with the Shrimps, O'Hara made his professional debut in a 3–1 defeat to league leaders Northampton Town on 23 January 2016.

[18] On 20 November 2021, O'Hara joined League Two side Scunthorpe United on an emergency seven-day loan deal following an injury to first-team goalkeeper Rory Watson.