Coach Ange Postecoglou says he has been encouraged by the way his players are adapting to his ideas after Celtic continued their promising pre-season campaign with a 2-1 win over Charlton at Newport, Wales.
First half goals from Karamoko Dembele and Albian Ajeti put Celtic in command at Dragon Park before former Hearts striker Conor Washington pulled a goal back late on.
"The first half was quite good, we controlled the game pretty well," Postecoglou told Celtic TV.
"In the second half it got a little bit stretched and chaotic but to be fair, for a lot of these guys it's their first game for quite a while but they worked hard and that's the main thing.
"Some of them looked a little bit rusty with their touch but that will come.
"We're working hard in training as well which probably has an effect in terms of fatigue in the games.
"The most important thing for me is they're trying to do the things we're talking about and as long as they do that we can progress."
Celtic next face Bristol City before opening their Champions League qualifying campaign against Midtjylland on July 20.
Scotland internationals David Turnbull, Callum McGregor, Ryan Christie and Greg Taylor all featured for the first time in pre-season as Postecoglou picked different sides for each half.
Olivier Ntcham also got 45 minutes of action along with new signing Osaze Urhoghide.