Club Cooney experienced much success at club hurling with Sarsfields. In 1980 Sarsfields qualified for the final of the senior championship for the first time in history, with Cooney lining out at midfield. The free-taking of Michael Mulkerrins secured a narrow 0–11 to 0–9 defeat of
Meelick-Eyrecourt and a
Galway Senior Hurling Championship medal for Cooney. He later added a
Connacht medal to his collection following a convincing 4–12 to 0–5 defeat of
Tremane. Almost a decade later Sarsfields were back in the championship decider once again. A 3–7 to 1–8 defeat of
Athenry gave Cooney a second championship medal. Three years later in 1992 Cooney was in the twilight of his club career. He won an
All-Ireland medal as a non-playing substitute following a 1–17 to 2–7 defeat of
Kilmallock.
Inter-county Cooney made his senior championship debut for Galway on 1 July 1979 in a 1–23 to 3–10 defeat of
Laois in the
All-Ireland quarter-final. He was an unused substitute for the subsequent All-Ireland final defeat by
Kilkenny. In
1980 Cooney was a regular member of the starting fifteen as Galway reached the
All-Ireland decider once again.
Limerick provided the opposition on this occasion and an exciting championship decider followed.
Bernie Forde and
P. J. Molloy goals for Galway meant that the men from the west led by 2–7 to 1–5 at half-time.
Éamonn Cregan single-handedly launched the Limerick counter-attack in the second-half. Over the course of the game he scored 2–7, including an overhead goal and a point in which he showed the ball to full-back
Conor Hayes and nonchalantly drove the ball over the bar. It was not enough to stem the tide and Galway went on to win the game by 2–15 to 3–9. It was Galway's first All-Ireland title since 1923, with Cooney picking up a
winners' medal and the celebrations surpassed anything ever seen in
Croke Park.
1981 saw Galway reach a third consecutive All-Ireland final and
Offaly were the opponents. Everything seemed to be going well for Cooney's side as Galway hoped to capture an unprecedented second consecutive All-Ireland title. Offaly 'keeper
Damien Martin was doing great work in batting out an almost certain Galway goal early in the second-half. With twenty-three minutes left in the game Galway led by six points, however, they failed to score for the rest of the game.
Johnny Flaherty hand-passed Offaly's second goal with just three minutes remaining. At the long whistle Galway were defeated by 2–12 to 0–15. Cooney's last game for Galway was an All-Ireland semi-final defeat by Kilkenny in
1982.
Inter-provincial Cooney also lined out with
Connacht in the inter-provincial series of games and experienced some success. In 1979 Cooney was at left wing-back as Connacht reached the inter-provincial decider. A 1–13 to 1–9 defeat by
Leinster was the result on that occasion. Cooney retained his place on the team in 1980 as Connacht faced
Railway Cup specialists
Munster in the decider. A low-scoring game followed, however, a 1–5 to 0–7 victory gave Connacht their first Railway Cup title since 1947. It was Cooney's sole winners' medal in the inter-pro competition. ==Refereeing career==