Damien has been working as a chartered physiotherapist since graduating in 2001. He completed a Masters in musculoskeletal physiotherapy in the University of Queensland in 2004.
Upon return to Ireland he worked for 2 years in Killarney during which he was team physiotherapist to the Kerry Senior Football Team who were All-Ireland Senior Football Champions in 2006. He returned to work in private practice in Limerick in 2007.
During this period he worked with Shannon RFC and commenced working with Munster Rugby in 2008, working with Munster A, the academy and Munster U20s.
Mordan joined the Munster medical team as Lead Physiotherapist at the start of the 2016/17 season.