Born near Kinsale, County Cork, O'Regan first played competitive Gaelic games during his studies at the De La Salla College in Waterford.
As a member of the Munster inter-provincial teams on a number of occasions, O'Regan won several Railway Cup medals as a dual player.
After serving as trainer with Courcey Rovers and St Vincent's, he trained the Cork senior hurlers to All-Ireland success in 1966.
Cork won on the third occasion with O'Regan collecting his first Munster Senior Hurling Championship medal.
The subsequent All-Ireland final pitted Cork against Kilkenny at a snow-covered Croke Park in October of that year.
That game ended in a draw, but in the replay Cork triumphed with O'Regan collecting his second Munster title.
Galway, who had received a bye into the final, were beaten on a scoreline of 6–12 to 1-0 and O'Regan won his second All-Ireland medal.
The subsequent All-Ireland final was a replay of the previous year's game as Cork played Galway once again.
In 1932 Cork set out to defend the Munster and All-Ireland titles; however, Clare defeated O’Regan's side on that occasion.
Partial Reference: Cork GAA website Inter-County SHC Results and Teams.
Partial Reference: Cork GAA website Inter-County SHC Results and Teams.
Partial Reference: Cork GAA website Inter-County SHC Results and Teams.
Partial Reference: Cork GAA website Inter-County SHC Results and Teams.