Fennelly first played
camogie to a high standard as a student at
Presentation Secondary School in
Kilkenny. After entering the Leinster Colleges SCC for the first time, the school reached the provincial final in 1966 but lost out to Oldcastle. The absence of a juvenile camogie scene meant that Fennelly first played at club level with
St Paul's in 1965. She won the first of three successive
Kilkenny SCC titles that year, while she also claimed a
Leinster Club SCC title in 1966. Fennelly later transferred to the
Celtic club in
Dublin and won a
Dublin SCC title in 1973. Fennelly returned to the St Paul's club in 1974 and won the first of seven successive Kilkenny SCC titles that year. She also won three Leinster Club SCC titles during this period, as well as
All-Ireland Club SCC medals in 1974 and 1976. Fennelly brought her playing career to an end after winning her 10th Kilkenny SCC title in 1980. At inter-county level, Fennelly first played with the
Dublin senior camogie team in 1972. She declared for
Kilkenny two years later. Fennelly won three
All-Ireland SCC medals in a four-year period between 1974 and 1977, as well as
captaining the team to victory over Dublin in the
1976 All-Ireland final. Her other inter-county honours include three
Leinster SCC medals and a
National Camogie League title. Fennelly also earned a call-up to the
Leinster team and won two
Gael Linn Cup medals. ==Administrative career==