Stephen Ferris thinks Ireland coach Joe Schmidt's reliance on out-of-form big names and an overly rigid game plan cost the side dearly at the World Cup.
"Going into this game I felt Ireland were going to get beaten, but I didn't see a 40-point hammering coming," the 2009 Grand Slam winner told 2fm's Game On of Ireland's tame quarter-final exit on Saturday.
"New Zealand were brilliant. Sometimes you've just got to tip your hat to the opposition, but at the same time there will be a feeling of massive disappointment.
"They cannot put this right in a couple of months time, this is another four years to wait, which is a long long time in professional sport.
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"The hope and expectation we all had 12 months earlier when we were beating the All-Blacks, we've just peaked that little bit too early.
"Joe was relying on his big-game players to come up trumps and some of those guys are struggling for form and didn't turn up. I haven't seen Johnny Sexton play a game like that in many a day.
I don't think this is just Joe Schmidt or the coaches' fault. They know they didn't perform and that's the biggest disappointment."
Co-host Donncha O'Callaghan thinks new players should have been blooded after England dominated at the Aviva Stadium in February.
"The wake-up call should have been when we lost so poorly to England in the Six Nations," O'Callaghan said.
"That should have been alarms to everyone because they cracked us and mentally broke us.
"We showed a weakness there and he needed to be there and make a few hard calls, and probably cull some players. But by the time we got to Saturday he had invested in those players and had to put them out."
Ferris would like to see Ireland move away from the famously structured Schmidt style under Andy Farrell.
"I don't think Joe and I would have seen eye to eye," said the Ulsterman. "I would probably have challenged him daily.
"He is so obsessed about the lads doing their own individual roles and responsibilities perfectly, and if one of those things goes wrong, then it's a nightmare and everything else goes out the window.
"I think he's got caught up in terms of 'if you win the percentages, you're going to win the match'. Sometimes you've just got to go out and express yourself.
"This young crop of players - someone like Stuart McCloskey at Ulster - has never got a look in because he's a little bit outspoken, he sometimes plays rugby off the cuff and doesn't always stick to the game plan if he sees something that's on in front of him. He'll back himself to make the right decision.
"Joe is like a machine, he codes something into the machine and if everybody does everything right, then they'll come out the right end of it with a score or the opposition on the back foot.
"I think now is a perfect time to change. Andy Farrell is there to be able to do that and I think there is going to be a massive change."
Follow the Rugby World Cup semi-finals this weekend via our live blogs on RTE.ie/Sport and the News Now app, or watch live on RTÉ2.