Mr O'Leary (65) collapsed with a heart attack at the Kaikorai Bowling Club yesterday morning when playing in the 60th Dunedin Festival Fours.
His skip, Graeme Allan, a retired security officer at Dunedin Hospital, was trained to use the defibrillator and was able to get Mr O'Leary's heart beating again.
When the ambulance arrived to take Mr O'Leary to hospital, St John officers praised the work of the bowlers.
When Mr O'Leary owned the Southern Tavern, he was a major sponsor who helped the Kaikorai club raise the $5000 for the defibrillator.
‘‘Danny had just drawn two superb bowls before he collapsed,'' Mr Allan said.
‘‘He has been a member of our club for 17 years.‘‘I was happy to be able to use the defibrillator to help save Danny's life.''
The Kaikorai team was leading 11-4 at the time and the game was immediately called off. Other games were halted while the ambulance officers did their job and took Mr O'Leary to hospital.
There was another medical emergency on Saturday when Kaikorai club member Bill Jackson suffered a stroke.
Both bowlers were in a stable state and they spent last night resting in Dunedin Hospital.
Mr Allan yesterday said every bowling club in New Zealand should have a defibrillator.