Rory Best has vowed his side will learn from their first foray into the Heineken Cup knock-out stages for the first time in 12 years and be back in the big time again next year.
The 1999 Heineken Cup champions led Northampton Saints at half-time, but eventually went down 23-13 at stadium:mk to miss out on a semi-final clash with Perpignan.
"That was one of the most physically intense games I have ever played in with Ulster. We are very, very disappointed, especially at forward because we let the game get away from us in the first 15 minutes of the second half," said Best.
"We dropped off a fraction and they put on the squeeze. It is fine margins between winning and losing at this level, but we came off the field wanting more of that kind of experience.
"It was a big step up from the Pool stages and our domestic league, but that's what we all want. We have to learn from this experience.
"It is no coincidence that the same teams keep cropping up in the Heineken Cup quarter-finals year in, year out. You have to learn how to take your chances when they come along.
"Saints didn't let us breathe in the first 10 minutes and we couldn't get to their line-out or maul. They are so good at what they do and you need a solid set piece to play against them."
Ulster coach Brian McLaughlin was proud of the effort from his players, but bitterly disappointed at seeing them slip in the second half.
"I thought we took our eye off the ball at the set piece in the second half. But it was a huge learning curve for us and there is a hell of a lot more to come from this Ulster team," said McLaughlin.