Born and raised in Blackrock, Barrett first played hurling to a high standard as a student at St Francis College in Rochestown.
Connolly was top scorer with 0-07 when St Francis College beat Hamilton High School by 1-13 to 0-14 to claim the All-Ireland PPS SBHC title.
[4] Connolly won a Cork SHC medal in October 2020 after top-scoring with 0-13 in the 4-26 to 4-18 extra-time defeat of Glen Rovers in the final.
Success in this grade was immediate with Connolly claiming Munster and All-Ireland U20HC medals in 2020 after respective defeats of Tipperary and Dublin.
[10][11] He made his senior debut in May 2021 when he scored two goals after coming on as a substitute for Shane Barrett in a 5–22 to 1–27 National Hurling League defeat of Waterford.