Horgan joined the Glen Rovers club at a young age and played in all grades at juvenile and underage levels.

On 20 November 2005, he was at right corner-forward when Glen Rovers faced Carrigaline in the Premier County Minor Championship final.

On 8 November 2008, he was at right wing-forward when Glen Rovers faced Duhallow in the Cork Premier Under-21 Championship final.

On 28 May 2005, having just turned seventeen earlier in the month, Horgan made his first appearance at senior level in a 0-13 apiece draw with St. Catherine's.

On 10 October 2010, Horgan lined out at full-forward in Glen Rovers' first Cork Senior Championship final in 19 years, however, Sarsfields won the game by 1–17 to 0–18.

On 12 October 2014, Horgan was at right corner-forward when Glen Rovers faced Sarsfields in the Cork Senior Championship final.

Lining out at centre-forward he top scored with 0–11, including eight frees, but ended the game on the losing side following a 2–17 to 1–16 defeat.

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.

On 25 June, he scored seven points from left corner-forward when Cork defeated Tipperary by 2–20 to 1–15 to win a third successive Munster Championship title.

He was later included on Cork's panel for the 2008 Munster Championship and made his debut on 8 June as a 68th-minute substitute for Niall McCarthy in a 1–19 to 1–13 defeat by Tipperary.

[13] On 11 July, Horgan lined out in his first Munster Championship final when he was named at left corner-forward in Cork's 2-15 apiece draw with Waterford.

[17] He later assumed the captaincy after an injury to captain Donal Óg Cusack ruled him out of the latter staged of the league and the championship.

[21] Horgan's red card and one-match ban were later rescinded following a successful appeal to the Central Hearings Committee.

[25] On 3 July 2014, Horgan won a Munster Championship medal after scoring eight points in Cork's 2–24 to 0–24 defeat of Limerick in the last final to be played at the old Páirc Uí Chaoimh.

Horgan won his second Munster Championship medal on 9 July 2017 after scoring thirteen points in the 1–25 to 1–20 defeat of Clare in the final.

[32] On 17 July 2018, he was voted as the PwC GAA/GPA Player of the Month for June as a result of "his usual unerring accuracy from placed balls and crucial scores from play".

[41] On 3 March 2013, Horgan won a Railway Cup medal after scoring nine points in Munster's 1–22 to 0–15 defeat of Connacht in the final.

[45] Horgan played no part in the second leg, but claimed a winners' medal as a non-playing substitute as Ireland won the two-game series on aggregate.

[47] On 25 October, Ireland won the two-game series on an aggregate score of 4–26 to 3–22, with Horgan claiming a second winners' medal.