Kyle Coetzer’s men went into the clash knowing victory might be enough to clinch a place at next year’s global event in England, but Ireland continued their recent dominance with an eighth win in the last nine one-day internationals between the sides.
The setback means Scotland need victory in their final Super Six match against West Indies on Wednesday to have a chance of qualifying.
Skipper Coetzer said: “They maybe got a few more runs than we had hoped but it was a good wicket and we felt we were in the game at half-time.
“But a couple of crucial moments in the match went against us and there were a couple of things that we perhaps didn’t get right. We have to get things right going into the next game.”
Chasing 272 for victory, Scotland suffered an early blow when Matthew Cross edged a delivery from Tim Murtagh to be caught by Gary Wilson at slip.
Coetzer and Calum MacLeod launched a counter-attack with a promising partnership, the former hitting Boyd Rankin for three boundaries in an over. However, the pair were just beginning to seize the initiative when MacLeod, having stroked a four and a six in his 21, went for another maximum and was caught on the boundary by Andy Balbirnie off Simi Singh.
Scotland’s hopes appeared to rest with Coetzer who looked in fine touch as he moved to an accomplished half-century.
The former Durham and Northants batsman would have had three figures in his mind when he reached 61 with seven boundaries and a six only for Rankin to return to the attack and shatter his stumps. When George Munsey, Craig Wallace and Michael Leask followed cheaply, the Scots looked out of it on 132 for six.
A half-century stand between Richie Berrington (44) and Safyaan Sharif (34) halted the Irish victory charge but when they departed in quick succession, Scotland had too much to do.
Mark Watt (31no) bludgeoned two huge sixes in an entertaining last wicket partnership of 38 with Brad Wheal to close the gap but Rankin (four for 61) had the latter caught behind.
Earlier Scotland failed to bowl a side out for the first time in the tournament but fought back well to restrict their rivals to 271 for nine.
They made the perfect start when Wheal struck in the first over to remove Paul Stirling for a duck with a smart return catch.
Wheal thought he had a second in his next over when he hit Balbirnie on the pads but the umpire turned down the lbw appeal. It proved a lucky reprieve for the batsman who made the most of it by going on to spearhead the Irish innings with a fine century.
Balbirnie lost his captain when Wheal clean-bowled Will Porterfield for 17 but partnerships of 138 and 58 with the O’Brien brothers, Niall and Kevin, put Ireland on top.
Balbirnie was content to play second fiddle as Niall O’Brien stroked 70 at a run-a-ball with nine boundaries before he was brilliantly run-out by Craig Wallace. And it looked as if Scotland might concede in excess of 300 when Kevin O’Brien thumped 46 from only 27 balls with two maximums.
Balbirnie, meanwhile, moved smoothly to 105 from 146 balls before he was trapped in front by Watt. His departure sparked the Scottish fightback as Ireland lost six wickets for just 30 runs in the closing five overs. Wheal ended with three for 43 while Sharif had two for 52, but the damage had already been done.