A 37-year-old rugby player died immediately after lining out for his club in a friendly fixture in Kilkenny on Saturday.
His eldest son played alongside him in the match at Kilkenny Rugby Club at Foulkstown on the outskirts of the city.
Mr John Byrne, of Troyswood, Kilkenny, collapsed in the dressing room after the game against Northern side Randalstown. He was immediately given first aid, but never regained consciousness.
He was rushed to St Luke's Hospital, Kilkenny, where he was pronounced dead 12 minutes later.
It is understood that he suffered a major coronary and the results of the post mortem examination carried out yesterday are expected to confirm this.
Mr Byrne's 18-year-old son, Richard, played alongside his father in the game, while his youngest son, Gavin, attended the match.
Mr Byrne was an employee of Kilkenny County Council, and was manager of a water treatment plant in the city.
He was married to Priscilla and the couple have three children Richard, Gavin and Rebecca.
A major club fundraising event due to take place in the Kilkenny Ormonde Hotel on Saturday night was cancelled.
Club PRO Mr Seán O'Shea described Mr Byrne as a leader on and off the field who had given more than 20 years of service to the club.
"He was a gentleman and had a great commitment to the club and to the people in it. We will miss him. At this time our thoughts turn to Priscilla and the children," he said.