Ireland midfielder Jayson Molumby felt his sides slow start to the second half was their downfall in Saturday nights 2-1 loss to Scotland.
Stephen Kenny's men started the game excellently and deservedly took the lead through a smart finish from John Egan.
But Scotland flew out the blocks after half time and scored just five minutes into the second half. The pressure piled on by the Scots in the second period eventually paid off, with Ryan Christie's late penalty sealing the win.
"It's obviously disappointing. I haven't really had the chance to process that defeat," said Molumby.
"We went in 1-0 ahead at half time and I thought we were very comfortable.
"But we just didn't start quick enough second half and it ended up costing us."
There was a stark contrast between the first half performance when Ireland were making all the running, and the second half showing were the home side grew into the game and looked more and more dangerous. Ireland's inability to keep up the intensity levels of the first half was the most frustrating aspect of the defeat for the West Brom star.
"I don't know to be honest, it's obviously still fresh and we need to look at it and analyse it.
"For me I just don't think we started quick enough, we knew they were going to come out quick at the start of the second half.
"It's disappointing for us."
Ireland had their moments in the second half and actually responded quite well to Scotland's equalizer. But the away side were left to rue their missed chances, with Troy Parrott missing a particularly big one, shooting tamely at Craig Gordon with the goal at his mercy when the score was 1-1.
"No I haven't had a view of the penalty, obviously that's something to look at as well.
"For me, the penalty shouldn't come about in the first place, we shouldn't have conceded the first goal so early in the second half.
"I think we had a couple of chances as well which we'll be disappointed with.
"We should've finished the game off."
It was a fiery contest from throughout. Within a minute, James McClean was being flattened by John McGinn, while Matt Doherty clattered into Kieran Tierney on a couple of occasions. The ferocity of the contest was a surprise to nobody who read quotes coming from the Scottish camp this week.
"No, obviously after what we done to them the last time we were expecting a tough game, a tough atmosphere.
"I thought first half we were excellent, well organised and we matched them in every battle and every second ball.
"It's just disappointing that it seemed to fade in the second half."
A dispiriting defeat leaves Ireland in what amounts to a relegation play-off with Armenia next Tuesday. Despite this, Molumby believes the squad have made huge progress in recent months.
"The last three games, Scotland 3-0, Ukraine we should win that game I feel one nil ahead, here tonight we should win.
"One nil up, should be two nil up maybe cruising.
"It's disappointing, but we'll take a lot of positives and try again against Armenia."
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