Ireland coach Joe Schmidt bemoaned his side's slow start to the game and missed try-scoring chances as they lost their Six Nations opener to Scotland.
Ireland trailed 21-8 at the interval but fought back to lead by one point, before going down 27-22 at Murrayfield.
"We were well off our game early on and the Scottish attack really took advantage of that," lamented Schmidt.
"We fought back and had some gilt-edged chances. It's incredibly disappointing that we let it slip in the end."
Scotland started strongly with two tries from Stuart Hogg and, though Keith Earls scored in the corner for Ireland, Alex Dunbar's score put the hosts 21-5 up.
Tries from Iain Henderson and Paddy Jackson put the away side 22-21 ahead before Greig Laidlaw's two late penalties sealed Scotland's victory.
Schmidt said defeat had been "tough to take".
"We arrived at the stadium 10 or 15 minutes late and we were late for most things in the first half," he added.
"I thought we clawed our way back well in the second half and shut down some of their attack but missed some good opportunities ourselves."
Schmidt said watching the game back would not be pleasant, particularly given the first-half defensive lapses which helped the Scots gain a foothold.
"We were very naive and passive in the early stages, which was something we had worked pretty hard to avoid," he said.
"We missed our timing a bit but we haven't played in a long time and there were a few changes in there too since our last game."
Under new rules introduced this year, Ireland secured a losing bonus point for finishing within seven points of their opponents, and Schmidt remains upbeat about their prospects.
"We're not out of the competition," he said. "We did get a point out of the game but given that we scored three tries, we are maybe disappointed that we were only one try away from getting another [for scoring four tries].
"At the moment our priority is to get recovered and work towards a much better performance next time."