Boss Craig Levein was left 'devastated' by Scotland's controversial late 2-1 defeat to Wales in Cardiff.
Scotland were 1-0 up thanks to James Morrison's goal when they had a second chalked off by the officials.
Charlie Adam's curling cross from the left was adjudged to have gone out of play before Steven Fletcher thumped home a header.
Levein said the decision was a "body blow" for the Scots, who conceded two late Gareth Bale goals and are second bottom of their Group.
He said: "As the game panned out that second goal was absolutely crucial and not getting it was a real body blow.
"That second goal was so important for us, and I believe the officials made a
serious error with the chalked off goal that Steven Fletcher scored. That is
very hard to take."
"When Wales equalised we didn't feel we were under enormous pressure at all. I'm amazed we have come in and lost. I didn't feel we were under any threat."
Levein admitted Bale made the difference: "We know how good a player he is. Once he gets into his flow he is very difficult to stop.
"From my point of view I am absolutely devastated. It is really difficult to take."