Celtic were left stunned after the 2-1 Champions League defeat at Aalborg which sent them crashing out of Europe.
When midfielder Barry Robson put Celtic ahead in the 52nd minute with a diving header it looked as if the Hoops might finally get an away win in the group stages of the tournament after 18 attempts and keep themselves in contention for a last-16 place.
But in the 72nd minute Caca drew his side level with a drive from 25 yards which deflected off captain Stephen McManus before looping over Artur Boruc.
Then after Gary Caldwell put through his own goal, Celtic were denied even the consolation of a UEFA Cup place to look forward to in the new year.
Like most of the Celtic players, defender Mark Wilson emerged from the dressing rooms with a haunted look.
He said: "This is probably the lowest point of my career. It was unbelievable. I can't get my head around how we lost that game. We were stunned, absolutely stunned. When we scored it looked like we could have gone on and increased our lead.
"We weren't under any pressure, so to lose two goals was hard to take. It was a deflection and an own goal which beat us. It was simply bad luck. Maybe we should have been strong enough to see the game out - but that might be over-critical.
"It does make it even worse that we are not even in the UEFA Cup. But we are still in a bit of shock at the moment.''
Robson remains confident that the elusive away win in the competition will come.
He said: "When you lose a goal to a deflection and ricochet, you think 'the gods are not looking down on us tonight'. I felt we were really unlucky - and we should have had a stonewall penalty when Scott McDonald was brought down in the box by their goalkeeper.
"But I thought we played well; we were 1-0 up and cruising the game, and I felt we were comfortable. It won't be a problem to pick the players up. We have strong characters in that dressing room and we will keep going - and we will get that away win eventually.''