Capped by the Republic of Ireland at under-18 and under-19 level, Mulhern started his career in the Huddersfield Town academy when he joined at under-9 level in August 2005.
After nearly four years with Huddersfield he departed for Leeds United in May 2009.
He subsequently turned professional with the Elland Road club in the summer of 2015 following a two-year scholarship.
However, he was released and re-joined Huddersfield’s under-23 development squad in February 2016, before joining Guiseley at the start of the current season.
Mulhern has also had brief loan spells with Southport and Alfreton Town.
He will be available to go straight in to the team for the Salford City game tomorrow.