Murtagh made his debut on the inter-county scene at the age of fifteen when he was selected for the Westmeath minor team. He enjoyed a successful tenure in this grade, culminating with the winning of an All-Ireland medal in 1999. Murtagh subsequently joined the Westmeath under-21 team, winning All-Ireland medals in 2000 and 2003.[2] By this stage he had also joined the Westmeath senior team, making his debut during the 2001 championship. Over the course of the next seventeen seasons, Murtagh won three Christy Ring Cup medals. He also won a National League Division 2 medal in 2008. Murtagh played his last game for Westmeath in November 2020.
After missing out on selection for the Leinster inter-provincial team through injury, Murtagh was included on the starting fifteen in 2009. He was a regular in several campaigns and won two Railway Cup medals.
He has been a Westmeath senior hurling selector.[3]