Ireland head coach Joe Schmidt admitted missing the opportunity to end 108 years of hurt against New Zealand was "devastating".
Having led 19-0 after the first quarter, Ireland were firmly in charge at 22-7 ahead at half-time as they looked to earn their first-ever win over the All Blacks at the Aviva Stadium in Dublin.
But Schmidt knew Ireland were "hanging on by a thread" when New Zealand levelled the scores in overtime through replacement Ryan Crotty.
Aaron Cruden's conversion sealed the All Blacks' 24-22 victory and their status as the first professional-era team to complete a perfect season.
But the Chiefs fly-half did so at the second attempt, with Ireland chasing his missed first kick early.
Ireland remain winless against New Zealand in 28 attempts and Schmidt acknowledged no amount of positive thinking about tries for Conor Murray, Rory Best and Rob Kearney can alleviate the deep dejection of a cruel defeat.
Schmidt said: "We were in possession with a minute to go.
"To be a minute away from history and have the ball in your hands on their 10-metre line, well it's devastating.
"I guess you sum it up as a step forward but a missed opportunity.
"You don't get too many opportunities to play the All Blacks and to stop them doing something that's pretty special.
"It would have been a feather in our caps to be the ones to knock them over.
"We lost a few guys with injury and we started to look a bit piecemeal out there.
"I thought we were pretty dynamic in those first 20 minutes and pretty good for the lead we made.
"They put a lot of pressure on us in the second-half and the defence in the end is disappointing but it's cumulative.
"We made a lot of tackles in the second half and that started to show.
"We were hanging on by a thread and the thread was just a little bit too thin to make sure we could stop them."
"They put a lot of pressure on us in the second-half and the defence in the end is disappointing but it's cumulative" - Joe Schmidt
Jonathan Sexton missed a 74th-minute penalty chance to put Ireland eight points to the good before New Zealand hit back at the death.
Schmidt said it was not worth taking issue with Cruden's retaken conversion that won the tie, and sealed New Zealand's 14-game perfect season.
He said: "A draw was as good as a loss to us.
"We haven't won in 108 years of trying against this opposition and we didn't want to just do what had been done before.
"If a player moves once he's stood still, our players felt he had.
"For me he'd already done it once, it wasn't so smart to do it the second time.
"If the referee's happy he hasn't started his movement towards the ball then he can award another kick.
"But it's not relevant for us here."
Captain Paul O'Connell challenged Ireland to carry their ferocity and aggression into the RBS 6 Nations after two defeats in three matches in the Guinness Series autumn schedule.
He said: "It's incredibly important that we recapture that for the Six Nations.
"There have been a few performances like that over the last two years, but then we don't carry it forward.
"And that's the huge challenge for us now.
"It's a really intense club period over Christmas now, so we've got to make sure we come back to Ireland for Christmas and the Six Nations ready to take things forward."