Ange Postecoglou saw his Celtic side beat Livingston 2-1 to restore their nine-point lead in the Premiership but felt his team could have done more in attack.
An own goal by Ayo Obileye and a goal from Kyogo Furuhashi put Celtic two goals up before Nicky Devlin netted for Livingston just before the break and the champions saw out the second half to take all three points.
However, having had 16 shots on goal in the first 45 minutes, Postecoglou felt his side should have been out of sight early in the game.
The Celtic boss admitted to a bit of frustration and said players weren’t carrying out the plan effectively.
“Obviously it was important to win but the performance was not one of our best, to be fair,” he said.
“I thought first half we controlled the game and did the things we wanted to do. I was disappointed that we created some good opportunities but we didn’t have people in the box doing their jobs. Balls were getting flashed across and people aren’t in the areas they should be.
“That’s disappointing because we work on that constantly and have had a lot of success playing that way.
“When it doesn’t happen I get frustrated because there’s no reason why it shouldn’t.
“At 2-0 the game should have been over but we conceded a soft goal, which again we’ve been good at not doing. We’ve been really disciplined at not giving away silly goals and I just thought we lost concentration for a moment.
“Second half was ok and I thought we controlled the game for the most part but there wasn’t a great deal of rhythm there. I guess we saw the game out.”
Livingston manager David Martindale felt his side could be reasonably happy with their efforts.
“We looked like we could get another goal from that 15-20-minute spell,” he said.
“We were very competitive in the game. My goalkeeper wasn’t as busy as I thought he’d be and I don’t mean that in a disrespectful way.”