George O'Callaghan celebrates with Cork team-mate Dave Mooney

O'Callaghan caught out home keeper Dwayne Nelson with an angled free-kick which sneaked in at the near post in the 17th minute at Stangmore Park.

Three minutes before half-time the City striker netted again after chesting the ball down and beating Harry McConkey.

Cork were on top in the second half but failed to add to their tally.

Late in the game Dave Mooney's fine run ended with a shot which came off the top of the crossbar.

Harry Fay's Dungannon now face an uphill task in qualifying for the semi-finals.

After the game, Fay said he thought Cork were "top notch from start to finish".

"They were further on than I thought they would have been at this time of year.

"We played them last year and thought we got closer to them then but we had a bit more quality at that time too.

"At 2-0 down at half-time we were in danger of getting a hammering so we had to roll up our sleeves and work that little bit harder in the second half.

"Hopefully our young players will learn from it and gain from it and we will just take every game as it comes and hopefully give a good account of ourselves.