A late Stephen McCavitt goal inflicted a harsh blow on the Mallards, who will feel they should have taken more from this game.
Whilst the visitors were dominant in the first half, Harry McConkey's men were the better in the second and passed up a bagful of chances.
Newry felt they should have been awarded a penalty early on when Conor McCaul was fouled whilst John McGovern also shot off target when well placed.
The Mallards were frustrated not to be awarded a penalty themselves by referee Barry Monaghan early after the restart when Ryan Campbell was fouled. A free kick was given right on the edge of the penalty area which McCartney hit the post with.
McCartney then himself was fouled in box which the referee appearing to play an advantage only for McIlwaine's shot to be blocked.
Campbell then tried his luck with a free kick which was deflected to the feet of McIlwaine but he couldn't find the target as the frustration grew.
Foley and Lavery both went close for the visitors who struck the only goal of the game late on to snatch an away win.
The Reserves however got off to a winning start with a 6-3 victory at the Bawnacre. Lorcan McGrady netted a hat trick with Shea Devlin, Lee Frazer and Henry Miskimmin also on the scoresheet.