Manager Ronny Deila said he will expect better from Celtic when they face KR Reykjavik in the second leg of their Champions League qualifier.
Callum McGregor's late goal gave Deila's men a 1-0 lead to take to Murrayfield, which will host the return while Celtic Park is unavailable.
"My philosophy is always to learn," said Deila. "We'll do that and perform even better at Murrayfield.
"I'm happy with the performance, especially the second half."
Celtic dominated the first leg of this second qualifying round encounter at the KR Vollur Stadium.
Kris Commons, Leigh Griffiths and Teemu Pukki all hit the woodwork before McGregor's deflected winner on 84 minutes sank the Icelandic champions.
"It felt a little sleepy in the first half, nothing much happened," Deila told BBC Scotland.
"In the second half, it was much better when we started to play through them with penetrating passes. We got more runs between them and opened them up.
"We've played four [friendly] matches and scored every chance we had. Tonight we didn't, but we created a lot. If it had been 0-0, I would have been happy as well because of the performance."
The match was goalscorer McGregor's first competitive start for the Scottish champions.
"It's a bit surreal but I'm delighted, first of all that the team got the win and on a personal note to get the goal," the 21-year-old said.
"Being in the Champions League makes it a bit extra special, but we've just got to focus on the return leg now."
Reykjavik defended resolutely and had a chance to score through former Celtic youth player Kjartan Finnbogason while it was still goalless.
Manager Runar Kristinsson played down their chances of getting a shock result in Edinburgh on Tuesday night but is not giving up hope.
"It was a wicked deflection for the goal, so a bit unlucky, but we got lucky a few times when they hit the woodwork," he said.