Dunfermline manager Stephen Kenny backed young goalkeeper Sean Murdoch to bounce back from the mistake that handed Hacken a Uefa Cup draw.
Stephen Kenny's side are now underdogs for the tie
"He has shown great promise and will be alright," Kenny said after the 1-1 draw in the first leg. "He showed that with a couple of good saves after that.
"We came out the traps strongly and the goal should have settled us down.
"But we lost two players in the first half through injury and they are a good side. On the night, a draw was fair."
Kenny insisted that Dunfermline could still go through despite having to score in Sweden if they are to progress to the next round.
"We're a bit disappointed with the result, but the tie is very much still alive," he told BBC Sport.
"Hopefully we can improve in the next couple of weeks after we have a couple more games under our belts."
Sean Murdoch was at fault for Haken's equaliser
Murdoch had come on after an injury to Roddy McKenzie after just nine minutes.
"It's hard when you are just thrown on off the bench for your debut," added Kenny.
"But he's got a lot of potential and has been in Scotland's under-age squads.
"It was a bit of a freak goal, I haven't seen such a goal.
"They are new balls. We have only had them two weeks and they are very light.
"They bounce like that sometimes. It was just a misjudgement."