Leinster have apologised after the Wolfe Tones song 'Celtic Symphony' was played following Sunday's win over Connacht at the RDS.
It has been reported the song was faded out after one verse and chorus as players did a lap of honour.
"A song was played over the PA at the RDS Arena this evening that shouldn't have been played," a Leinster spokesperson said.
"Leinster Rugby has taken measures to ensure it doesn't happen again and apologises sincerely for its use and for any offence caused."
The Republic of Ireland women's football team previously apologised after a video emerged of players singing the chorus of the same song after qualifying for the World Cup.
Uefa fined the Football Association of Ireland 20,000 euros after the game at Hampden Park in October, and described the incident as "a violation of the basic rules of decent conduct".