Eddie O'Sullivan says one of the most worrying aspects of Ireland's loss to Japan was they surrendered a winning position that had been established in the opening quarter.
After Rob Kearney touched down in the 22nd minute, Ireland led 12-3 but they failed to score for the remainder of the game.
Things started to go awry from the half hour mark, a Rory Best overthrow on a lineout seemingly the trigger for a Japanese revival.
Speaking on the RTÉ Rugby World Cup podcast, O'Sullivan said it was like watching a team "dismantle itself in slow motion."
This is especially worrying, according to O'Sullivan, because it is atypical of Ireland, especially Joe Schmidt's Ireland.
Over the years, Ireland have struggled to dig themselves out of losing positions but under Schmidt, they have been exceptionally good at tenaciously maintaining hold of winning positions.
This was not achieved on Saturday.
"The first 25 minutes we were not afraid of anything. We played some great rugby. Ringrose had two cracking breaks, we had two tries scored, we were dominant in the scrum. Even from the restart from the second try, Carty cross-kicked to Earls and we were 60 metres up the field. It was all on.
"Then we got sloppy and we had a couple of penalties pinged against us. And suddenly it's 12-9 at half-time.
"And in the second half, we strung together bad moments where we had them and needed to score and take the fizz out of them. We lost a lineout, we had the grubber that O'Mahony put through and Earls missed a tackle and suddenly they (Japan) were up the touchline.
"Then it started really going downhill with the collision between Farrell and Stander which led to the scrum which led to the try.
"We're now in trouble. We had a couple sorties where we did slow down the game. We played phases across and kicked the ball away. We just lost our mojo. At one stage, we had a four on two overlap and Carbery carried the ball into contact. It had panic written all over it.
"It was like a team dismantling itself in slow motion in front of us. That is a worry.
"You could say with Ireland across the board over the years - we're not particularly good at digging ourselves out of a hole. We just tend to buy a new shovel and get on with it.
"I don't think that goes away. I think it's there at the moment.
"Joe Schmidt's teams have been great at grinding out results, getting in front, shutting you out and squeezing the life out of you.
"When we needed to squeeze the life out of Japan at the weekend, we strung together a series of errors and breathed life into them.
"That is a worry. It's not a worry against Russia. I can't imagine it's going to be a worry against Samoa.
"We saw it four years ago, when Argentina got us early doors, put us under the cosh, we never recovered. That's maybe part of our DNA. Maybe Joe Schmidt can't change that.
"In his era, we've been good at not putting ourselves in a hole. We were in a hole last weekend and couldn't find our way out. We dug even deeper, if anything."
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