A barrister has claimed Ireland will be a testing ground for how sport is affected by Brexit if Britain crashes out of the European Union.

Tim O'Connor BL told a seminar organised by the Sports Law Clinic at University College Cork that top-level rugby could be most immediately affected, while UCC economics lecturer Dr Robert Butler said horse racing could also be impacted by Brexit.

Mr O'Connor said domestic sport in Ireland currently operates across two EU member states, that players in professional sports move without any hindrance and that the border does not exist in many sports.

He said much sport in the north is run out of a different EU State.

Taking rugby as a case study he said freedom of movement was fundamental, particularly in an all-Ireland structure which allows players to move between provinces to improve their game time.

However, in the event of Brexit he said: "Northern Ireland, as it stands, becomes part of a third state."

"Domestic sport in Ireland will be between the EU and a third state."

"Ireland is the test bed," Mr O'Connor said.

Every sport and Brexit issue arises in Ireland. They will arise literally the next morning. The clashes caused will set the model for how the EU law of sport interacts with Brexit.

Dr Robert Butler spoke to the seminar regarding how horseracing is supported annually and how this money is generally distributed, placing that in the context of Brexit and considering issues such as the tripartite agreement between Ireland, Britain and France, and customs and taxation problems that may emerge.

He also spoke about the exportation and importation of horses between Ireland and Britain, and the subsidy that race courses in the North of Ireland currently receive from Horse Racing Ireland.