Celtic manager Ronny Deila has been analysing his side’s defeat to Dinamo Zagreb in the Europa League Group D on Thursday.
The Bhoys took the lead in Zagreb midway through the first half, but they ended up losing the encounter 4-3.
The performance of Celtic was not brilliant, but that did not prevent them from progressing to the round of 32 in the competition.
Nevertheless, Deila was disappointed with his players and is quoted as saying by BBC Sport: "I think it was a poor performance. They were not 100%.
"There was a lack of the intensity and aggression that we had against Motherwell. The substitutes were very positive when they came on and that was what was good in the game.
"But the defence gave away too many chances and you should win if you score three goals away from home in Europe.
“We have the players to produce good defending, but is more how we play as a team and how we play away from home.
"Individually, there were some bad performances, but collectively we were too open. We will have to be a lot better in the next round and there are players to come back who were not involved today.”