Ronny Deila has praised his Celtic players for not slipping up in their 2-0 victory over Raith Rovers in the League Cup.
Despite being pushed all the way by the Championship side, Deila claims that it was pleasing to see the holders overcome some difficult spells to reach the quarter-finals.
"I am always a little bit worried. You never know in football and the Cup is always like that. When it is 1-0 anything can happen but I think we were in good control and it was good that we got the second goal," the Celtic boss told reporters.
"When you meet a team from a lower division it is always difficult because they gave 110% and sometimes it is easy to get a bit lazy, if I can say that.
"But I think our players worked really hard for 90 minutes. We kept the pressure on all the time and could have scored more. We kept another clean sheet which is very important."
Celtic return to league action against Hearts on Saturday.