Pundit Michael Stewart insists Celtic shouldn't have been "hanging everything on" the controversially disallowed goal against Hearts.
The Parkhead club lost their opening league match for the first time in 24 years as Ange Postecoglou 's reign hit another early bump in the road.
However, it could have been different had Liel Abada's strike, with the game poised at 1-1, not been ruled out for offside.
Greg Taylor was flagged by the linesman as he crossed the ball, leaving John Souttar to become the hero late in the day at Tynecastle.
While Stewart admitted on BBC Sportscene that the goal was onside, he took aim at a poor Celtic showing against Robbie Neilson's Championship winners.
The pundit said: This is a goal, there is no doubt about it.
" Greg Taylor is onside here. He is played onside by (John) Souttar and Michael Smith. It’s very, very tight.
"These incidents can go against you on occasion.
"It’s very unfortunate, but if they are hanging everything on marginal decisions like that I think that tells you everything you need to know.
" Ange Postecoglou said it himself. They weren’t clinical enough in the final third and they are lacking.
"Their starting eleven, never mind the squad, needs to be strengthened. Huge amounts of work is needing to be done.
"There is so much scrutiny, with every work you say; Postecoglou in his post-match interview is talking about people trying to make things out to be different from what they are.
"Well, when he says he wasn’t forceful enough, these are things that can be interpreted in different ways.
"This is what happens at Celtic if you are not getting results."