He may be turning 85 years old this November but Denis O'Connor is no pushover.
The great-grandfather was in a race betting shop in Cork, Ireland, last Saturday (Sept 15) when three masked robbers rushed in bearing a sawn-off shotgun and hammers.
The masked youngsters demanded cash from the safe.
CCTV footage showed the thugs threatening shop manager Tim Murphy with their weapons.
Murphy grappled with one of them after he climbed over the service counter. He managed to shove him against a swivel chair and prevent him from attacking with his hammer.
Seeing Murphy surrounded by robbers, O'Connor came to the shop manager's rescue and proved that he was no ordinary punter.
The 85-year-old fended off a robber who swung a hammer at him and drove the chap out of the shop. He dodged another robber's attack and tripped him on his way out.
"When I saw them confronting Tim, I just acted," the elderly man told the Irish Independent.
A third robber carrying a shotgun panicked at the sight and fled the scene.
Local police are now on the hunt for the suspects who are believed to have escaped in a black saloon car.
Despite the scare, no one was injured in the incident.
A video clip of the incident has since gone viral on the Internet with netizens praising the elderly man for his courageous act.
"Sometimes you can just sit down and do nothing or you can stand up to people like these and that's what I did," O'Connor told the Irish Sun.
However, local police superintendent Mick Comyns warned: "It was great that a robbery was stopped but it could have been a very different story if the robbers stood their ground."