Pirates had a bright first stanza, with Gabadinho Mhango fiiring home the opener in the first quarter-of-an-hour but they could not hold on in the second stanza as Siphelele Luthuli snatched the equaliser for Celtic in the last nine minutes.
"I think the first-half was good, we had the combination that we make in the training session, we can see this but the second-half was not so good for us," Zinnbauer told SuperSport TV.
"I think we had the control of the game yet the opponent is coming, they make always a little more than me [us], maybe we thought in the first-half it was too easy for us and then you don't come back with the confidence and say, 'OK, it's easy' but it's not easy."
The German tactician added that they are still going through the process of building the team and they will improve with time.
"You see it was a very good second-half from the opponent but we'll work, it's a process and we'll come back and be better. It's a process, we had a little more than two weeks, we work together and we see many things making the sessions but for me it's not 100 percent. We'll have time, we have to work and improve the team."