A young entrepreneur who headbutted another man on a nightclub dance floor claimed the victim called him a "C***k f**k" after they bumped into each other.
James Putthaaree (25) "overreacted" to the alleged racial slur when he struck the man, inflicting dental injuries that required treatment costing thousands of euro.
Putthaaree, of Ballybay, Co Monaghan, but with an address at Charleston Road, Ranelagh, pleaded guilty to assault causing harm.
Judge Michael Walsh adjourned the case for a restorative justice report after the accused paid €6,000 in compensation.
Dublin District Court heard the incident happened at Dicey Reillys on Harcourt Street on November 29, 2017.
The victim, an accountancy student, collided with Putthaaree on the dance floor and the accused immediately headbutted him, knocking him to the floor.
The victim, whose teeth were displaced, had spent €3,350 on treatment and expected the future total to be €11,000.
Putthaaree, who had no previous convictions, was at the club with friends and while leaving, the injured party "shouldered him and called my client a 'C***k f**k'," defence solicitor Mary Arnold said.
He accepted he overreacted to this racial slur, she said.
Putthaaree was a software sales assistant at the time but had since returned to Monaghan and started out on a new career with a start-up fitness and food business, Ms Arnold said.
He had brought €6,000 to court in compensation.
Judge Walsh said "significant dental damage" was caused to the victim, who had to wear braces for a time and was left with "problems biting".
While the precise nature of the future treatment was unclear, it was undoubtedly "a very serious injury", he said.
The victim had felt self-conscious when people asked why he needed braces.
Judge Walsh said the accused was of previous good character and had shown genuine remorse. He adjourned the case to a date in May.