Brendan Rodgers felt Celtic lacked the firepower to get any more than a point from their 0-0 draw against Rangers at Ibrox.
The Hoops fans turned on the club's board following their embarrassing Champions League play-off defeat to Kazakh side Kairat Almaty on penalties on Tuesday night following two goalless draws, criticising them for not bolstering their squad with appropriate quality before such a crunch tie.
With Swansea-bound Republic of Ireland striker Adam Idah missing for the trip to Govan - as well as former Ireland U21 international Johnny Kenny - Michel-Ange Balikwisha was handed his Celtic debut, while Daizen Maeda led the line and then Shin Yamada came on later in the game.
Rodgers admitted it was a poor game, albeit the Hoops remain six points clear of Rangers after four fixtures going into the international break.
He said: "I thought it was a poor game, to be brutally honest.
"The positive for us, we haven’t given away much over the course of pre-season and today I don’t think we had a shot against us on target.
"So defensively, we’ve been there. We’ve been good and solid and lots of endeavour, which is great.
"But in terms of our quality in the game, it’s not at the level I’d expect a Celtic team to be.
"So, so that was a disappointment, but felt overall the quality of the game wasn’t at a high enough level.
"I think it’s about profile of player. I think I’ve been very clear on that.
"Guys are working well and working hard. But sometimes in teams you don’t quite have that feeling going into a game that you can score goals, like we were, this period last year.
"The team then goes in with a different energy and a different feeling which then sparks everything off and brings that energy and that real key attitude that you want.
"When you are lacking that, that (no goals) is sometimes what you get."
