Celtic's victory over 2-0 win against Lowland League side East Kilbride in the Scottish Cup was "Crucial", according to manager Ronny Deila.
Following back-to-back losses to Ross County in the League Cup and Aberdeen in the Premiership, the Norwegian was relieved to reach the last eight.
"I think it would have been very hard had we lost today, I admit that, so it was a crucial victory," he said.
"I will give a lot of credit to East Kilbride, they fought really hard."
Celtic were a goal up after 20 minutes when Leigh Griffiths diverted the ball past goalkeeper Matt McGinley with his arm from a yard out.
Deila's side did not look troubled by the minnows but their only other goal of the match came five minutes into the second half when Colin Kazim-Richards stabbed the ball over the line from close range.
The Celtic manager continued: "You never know in football but that would have been the biggest surprise in a lot of years. But it didn't happen and I am very happy for that.
"I thought we controlled the game pretty well, we could have created more.
"I didn't think we were accurate enough and I think the surface was a little bit difficult for us. We also have some new players and new relationships in the team so we could have played better, but we went through and that is the most important thing.
"We wanted to score more goals and we had our chances but nobody will remember that if we win the cup."
East Kilbride manager Billy Ogilvie described the match as "probably the proudest moment I have ever had in football".
He said: "It is pretty difficult to put into words. I am so proud of them but I think I am even beyond that.
"To an absolute man they worked ever so hard and they kept their discipline, it was phenomenal.
"When you make Celtic score their goals from set-pieces, you must be doing something correct in open play and that is how well we did today in open play.
"We closed Celtic down and made them work hard."