Northern Ireland's women were beaten for the second time in five days as the Republic of Ireland deservedly won the World Cup qualifier at Mourneview Park.
The opening goal came in first-half stoppage time when Northern Ireland's Rachel Furness headed Megan Campbell's long throw into her own net.
Campbell's 69th-minute long-range shot sealed victory for the visitors.
Defeat means Northern Ireland remain without a point, having lost Friday's opening qualifier in Norway.
It was the Republic's first competitive match under new manager Colin Bell.
They face a tough task to qualify, having been drawn in a group including top seeds Norway and European champions the Netherlands.
Group winners go through to the 2019 finals in France, with the best runners-up taking part in play-offs.
Northern Ireland, 60th in the Fifa rankings compared to the Republic's 27th, had some lucky escapes before conceding right at the end of the first half.
Republic defender Diane Caldwell headed just over following a corner, then Stephanie Roche's close-range effort was well blocked by Julie Nelson.
The home side had a further let-off in the 39th minute when Louise Quinn's goalbound header was inadvertently cleared off the line by team-mate Caldwell.
Northern Ireland were denied the opening goal when Kendra McMullan's strong 43rd-minute header was superbly tipped over the crossbar by Marie Hourihan.
Campbell had caused the Northern Ireland defence lots of problems with her long throws and, seconds before the half-time whistle, one of them produced the breakthrough as Furness headed into her own goal.
After the break, Roche had the ball in the net but was denied by an offside flag, then NI keeper Lauren Perry made a fine save at the near post to keep out a Quinn shot.
However, the 16-year-old was beaten in the 69th minute when Campbell's shot from well outside the area dipped over the keeper and into the net.
The Republic suffered a late setback, though, as Sunderland striker Roche, runner-up in Fifa's goal of the season award three years ago, was carried off on a stretcher with a knee injury.
N Ireland Wom
- 7MilliganSubstituted forBrennanat 68'minutes
- 4MontgomerySubstituted forMcCarronat 81'minutes
R. of Ireland Wom
- 3CampbellSubstituted forTolandat 82'minutes
- 8O'GormanSubstituted forKiernanat 21'minutes
- 11RocheSubstituted forBarrettat 90'minutes
- 21O' Riordan
- Vesna Budimir