A man assaulted his female friend's estranged partner with a golf club, a court heard.
Darius Ruzgys (37) left the victim with bruising to the face and damage to his teeth following the roadside attack.
Judge Dermot Dempsey adjourned sentencing to March to allow Ruzgys save €1,000 compensation for the victim.
The defendant, with an address at Ashvale Court, Duleek, Co Meath, was found guilty before Swords District Court of seriously assaulting the man at Bremore Castle in Balbriggan on December 18, 2014.
The victim said it was his birthday and he had contacted his ex-partner because he wanted to celebrate with his child.
She told him to call around to her house around 6pm, but she wasn't there when he arrived, and when he contacted her again she told him to come back at 10pm.
He said he returned at 10pm, and saw his ex-partner and the defendant getting out of a car.
He claimed Ruzgys didn't talk to him but came at him swinging a golf club and hit him on the face.
He said Ruzgys tried to hit him a second time but missed.
The victim said he then called to a friend's house, and called an ambulance and gardai.
A court heard the golf club was a nine-iron. In his evidence, Ruzgys claimed the victim was shouting at him and his former partner, shouting "I'll kill you b*tches".
He also had his arms up and his fists clenched.
Ruzgys claimed the victim ran towards him and he picked up the club to protect himself and the victim's former partner.
Ruzgys claimed he was afraid that if he didn't stop him he would hit his ex-partner.
Defence solicitor Donal Quigley said Ruzgys accepted he had hit the victim, but claimed it was in self-defence.
Finding Ruzgys guilty, Judge Dempsey said he was not satisfied the defendant's use of force was reasonable.