He then played for several clubs in the North East of England, including Blyth Spartans, before attracting the interest of Celtic.

Both associations, the Northern Ireland–based IFA and the Irish Free State–based FAI, claimed jurisdiction over the whole of Ireland and selected players from the whole island.

But although he may well have had family there, it has been established by the programme editor at Brentford FC (a former club) that he was born in Ushaw Moor, County Durham.

There is speculation that he may have concocted the story about Kilcock in order to be eligible to represent the two Irish Associations (a parent or grandparent was not sufficient to qualify in those days, it had to be birthplace).

[9] O'Brien was playing for four different clubs – Derby County, Walsall, Norwich City and Watford – when he won each of his four FAI caps.

The game also saw him, together with, Tommy Muldoon, Harry Duggan and Joe Kendrick, become one of the first four English League based players to represent the FAI XI.

The now veteran O'Brien put in a commanding performance as he captained a young FAI XI that included Paddy Moore, Alex Stevenson and Jimmy Kelly to a 2–0 win.