Ukraine coach Mykhailo Fomenko said his players "weren't prepared enough mentally" and "underestimated the effort needed to get victory" as they slumped to a surprise 2-0 defeat to Northern Ireland.
Ukraine put in a solid performance in the Group C opener against Germany, even if they lost 2-0 to the world champions, but their hopes of progress ended once Germany and Poland played to a draw later in the day.
Northern Ireland claimed their first win in a major tournament since 1982 after Gareth McAuley headed home from Oliver Norwood's free kick four minutes after half-time, and substitute Niall McGinn added a second late on.
Even fefore their elimination was final, Fomenko said his players had fallen far short of his expectations.
"The players were not united today," he told a news conference. "They didn't fulfil their requirements -- especially in terms of our formation, and how we played set pieces.
"As far as our opponents are concerned, nothing surprised us. We expected this type of football. I think of the 16 goals they scored in qualifying, nine were from set pieces, so we knew that and we prepared for this kind of football.
"We made major mistakes on the pitch. We weren't prepared enough mentally. Perhaps our players overestimated the opponent and underestimated the effort needed to get victory. We allowed them to play their own football -- that's why we lost."
Updated SPI projections to advance, Group C:
99.9% Germany (4 pts)
99.9% Poland (4)
76% N. Ireland (3)
-- Ukraine (0)- Paul Carr (@PCarrESPN) June 16, 2016
Ukraine play Poland in their final game but Shakhtar Donesk midfielder Taras Stepanenko knew their chances of progress are over.
"It's clear that it was a do-or-die game today and it seems clear that we're out of the tournament," he said. "The last game is not going to have any special value for the tournament, just for the prestige."
He added: "The game was on until the goal went in -- whoever scores first wins. That's the way it happened, because Northern Ireland had a lot of men back in defence and we knew that they had scored 80 percent of their goals from set pieces.
"We worked on set pieces all week, and now we conceded from one. What can I say? This is going to be a great experience for us, because when every game is so important, we have to be more careful, more focused and make more of an impact on the pitch.
"Unfortunately we didn't manage to do that today and if we look at the work rate, it seems that Northern Ireland wanted to win more than we did."