Steve Hansen says Ireland are struggling with the pressure of being "the top dog" since beating his All Blacks side in November.
The New Zealand head coach labelled Ireland the best team in the world and World Cup favourites after that game, but Ireland have struggled to replicate that level of performance since then.
Joe Schmidt's team sit third in the Six Nations table, having lost to England, 20-32, in Dublin, before unimpressive away wins in Scotland (22-13) and Italy (26-16).
Hansen says Ireland are now "the hunted" and lack his side's experience in dealing with that pressure.
"I said it at the time when we played Ireland that whoever won that game was going to be viewed as the number one team in the world and everyone is going to chase them," Hansen told local media.
"For us that's something we've been used to. We've been ranked the number one team for 112 months now, I think, but people have seen Ireland as the top dog after they beat us, and that put a massive amount of expectation on the players and coaches.
"Instead of being the hunters they are the hunted and it's different.
"It's different when you're sitting at the top of the tree. It's a different experience. Not many teams cope with it that well."