Celtic came through the second qualifying round against Rosenborg with a 3-1 aggregate win despite being without defenders Jozo Simunovic, Dedryck Boyata and Mikael Lustig and injured forwards Moussa Dembele and Leigh Griffiths, some of whom will be back to face AEK Athens next week.
Rodgers, whose only summer signing, Odsonne Edouard, was at the club on loan last season, said: “There is some work going on behind the scenes but there is nothing to give any clarity on anyone coming in.
“I think every manager and coach will always look and think they always need more. I want it for the supporters, I want it for the squad, but I want quality. We could have had lots of players in but we only want quality.”
Celtic have lost Stuart Armstrong to Southampton and failed with several bids for Hibernian midfielder John McGinn, but Rodgers accepts the need to wait.
He said: “This is a group that has continually grown and developed over these last few seasons, players that are really improving.
“To bring players in that are better than that, it takes a bit of time to source those. Not only that, it’s to get the deals done with those types of players.
“I’d be very disappointed come the end of August if we weren’t stronger as a squad. I’m happy with where we’re at at this point in time because essentially I have to work with the players that are here and try and get over what is a real treacherous period in relation to games and everything that comes with qualification.
“We’ve got a good squad here for that but we always want to improve and strengthen and that’s something that we would certainly want to do.”