Ireland suffered a shock two-wicket defeat to Oman in their ICC World Twenty20 opener in Dharamsala.
William Porterfield's men were unable to defend 154 for five, and 14 runs in Max Sorensen's final over, as Oman marked their debut in a global tournament by sealing a nail-biting success with two balls to spare.
Sorensen failed to control his yorkers under lights, serving up an initial no-ball to put Oman back in with a chance before another stump-high delivery sped away for four-byes to seal the outcome.
Oman's stands of 69 for the first wicket and then 47 for the sixth, after five had gone for only 21 runs mid-chase, led to the thrilling finish in a fluctuating contest.
The defeat is a significant setback to an Ireland team used to inflicting upsets themselves at major tournaments.
Porterfield insisted nonetheless that they can still put things right if they respond well in two remaining Group A fixtures.
"It's very disappointing and hard to take - but to a large extent, it's still in our own hands," he said.
"We've done a lot of good things coming into this first game. We didn't get it quite right today, but we've got to address it come Friday (against Bangladesh), and I think that's more mental than anything ... as long as Oman lose a game, then it's still in our own hands.
"It'll come down to run-rate. We've got to win two games, but that is what it is - and we're going to have to keep an eye on it."
Porterfield refused to cite the high-profile occasion or dew, and the possibility of a wet ball, as excuses.
"I wouldn't say pressure - a lot of the lads have been there and done it in that scenario," he said.
"Whether the ball was slippery at the end, I'm not sure. If it was then you've got to let the umpires know to change it.
"That's not an issue - it's dewy, we know that, we knew it was going to be the case. We just didn't get it quite right in those last four or five overs."
Ireland had to work hard for their total against a varied attack in an innings most memorable for the brilliant one-handed catch at cover by Zeeshan Maqsood to see off Paul Stirling and break his opening stand of 48 with Porterfield.
Top scorer Gary Wilson (38) had fortune on his side, until his was the first of two wickets to fall in the same over to Munis Ansari (three for 37).
The slingy seamer had conceded 11 runs from his first two deliveries - but when he returned for his second over he had Niall O'Brien mistiming to short fine-leg and then Wilson missed an attempted big hit and was bowled.
Ireland nonetheless eked out a par total, but Oman openers Maqsood and Khawar Ali put it well within range.
Kevin O'Brien took the pace off with his cutters on a used pitch and both openers chopped on - Khawar departing with an angry swish of his bat perilously close to the medium-pacer in his follow-through celebration.
Off-spinner Andy McBrine then took two wickets in four deliveries.
But just when it seemed Ireland were in control, sixth-wicket pair Jatinder Singh and Aamer Ali had different ideas.
Oman were right back in it after Tim Murtagh conceded 20 runs in the 17th over - including three successive fours to Ali - and despite more twists and turns, Ireland eventually came unstuck.
Oman and Bangladesh, who beat Holland by eight runs on the back of Tamim Iqbal's unbeaten 83, are therefore the early frontrunners to qualify.