Club Niblock played his underage football with home-club
O'Donovan Rossa Magherafelt and soon progressed to the club's
Senior team. For the seven years he was in the United States between 1971 and 1978, Niblock played for a variety of clubs. In New York he played for the Monaghan club, before later transferring to Sligo. He won Championships with both teams. When his team wasn't in action on certain weekends, he'd go to play for clubs in the likes of
Chicago,
Philadelphia or
Boston, for example he often played for Tyrone in Philadelphia. When he moved back to Ireland in 1978 Niblock played with Intermediate Cork side
Douglas for a while. While there he travelled home and helped Magherafelt win the 1978
Derry Senior Football Championship. It was the Magherafelt's first county title in 29 years. It is a breach of the rules to play for two clubs in different counties at the same time, but as Niblock says "I couldn't resist it. Three of my brothers were playing in that final and it gave me a great thrill to win the Championship alongside them". That minor indiscretion deprived him of the opportunity to play for Cork, but he has no regrets. He was later advised that
Nemo Rangers were a more football orientated club than Douglas and he soon transferred to them. His honours with the club include ?
Cork Championships, ?
Munster Club Championships and two
All-Ireland Senior Club Football Championships (1982 and 1984). He retired from club football in 1992.
Inter-county Niblock first came to prominence as part of the Derry
Minor side that won both the
Ulster Minor and
All-Ireland Minor Championships in 1965, beating
Cavan and
Kerry in the respective finals. He played at centre half forward on the team. The success was Derry's first ever All-Ireland Minor title. Three years later he helped the Derry
Under-21 team win both the
Ulster Under 21 and
All-Ireland Under 21 Championships. Having reached the Ulster Under 21 final, they beat
Monaghan. In the All-Ireland semi-final Derry defeated a fancied
Kerry team with ease. In the All-Ireland final Derry met
Offaly in
Croke Park and won 3–09 to 1–09, with Niblock scoring 1-01 from centre half forward. The success was Derry's first ever All-Ireland Under 21 title. Niblock made his Derry
Senior debut in 1966, while still a Minor. In 1970 Niblock helped Derry win the
Ulster Senior Football Championship, overcoming
Antrim in the final. Derry met Kerry in the
All-Ireland semi-final, but were defeated. The following year Derry lost to
Down in the Ulster final. Niblock scored 2-04 from play, a record which was overtaken by Tyrone's
Frank McGuigan in 1984. Later that year he emigrated to America, interrupting his inter-county career. He flew home from New York to play for Derry in the 1972-1973
National Football League semi-final against Kerry in
Croke Park. It was Niblock's last game for the county. Niblock was later selected to play for
Cork, but couldn't due to the indiscretion about playing for two clubs at once (see above).
Province Niblock represented
Ulster and won a
Railway Cup with the province in 1970. ==Coaching and managerial career==