Horgan first played for Cork as a member of the minor team. He was an unused substitute throughout the 2004 Munster Championship, but claimed a winners' medal from the bench after a 2-12 to 3-08 of Tipperary in the final. On 15 August, Horgan made his first championship appearance when he came on as a substitute for Eoghan Murphy in Cork's 2-15 to 1-13 All-Ireland semi-final defeat by Galway.
