Former Celtic forward John Hartson questioned Ange Postecoglou's team selection and setup in the wake of the Parkhead side's 3-1 defeat to Bodo/Glimt.
Hartson's old side have it all to do in the second leg of the Europa Conference League tie as they go to the Arctic Circle trailing by two goals.
Runar Espejord's sixth minute opener on his debut set the tone as the brilliant Norwegians showed no signs of rustiness two months out from their last competitive game.
Amahl Pellegrino added a second before Daizen Maeda's glanced header gave Celtic some hope.
But two minutes later a deflected strike from Hugo Vetlesen looped over Joe Hart and restored Bodo's advantage.
Speaking on BT Sport Hartson said: "A very disappointing evening. I thought the endeavour and willingness was there from the players, they gave absolutely everything.
"When you talk about quality, Celtic have quality in abundance. It just didn't happen for them tonight.
"You might question... Ange might look at himself in terms of the system that he played and the personnel.
"Because within 10 minutes of the second half, Hatate has come on, Rogic has gone off, O'Riley ended up going off.
" Jota, again, lots of endeavour and lots of the ball but it was just one of those nights.
"Every time Bodo/Glimt went forward they looked a threat, they're a very good side and Celtic are up against it."
Hartson was particularly disappointed with the performance of Greg Taylor, who was beaten far too easily down the side by star man Ola Solbakken for the visitors' second goal.
He continued: "O'Riley does well, he works back so Celtic are two versus one defensively but Greg Taylor's got to show him down the line.
"He's cut inside so, so easily. Look at this, this is so feeble from Taylor.
"Watch, how easy is that?! Show him down the line, your body angle is in the wrong shape for a start. He cuts inside, that is just far too easy.
"And then you've got Pellegrino on the back post, Juranovic switches off, look at him trying to play offside when Pellegrino is three yards in front of him. It's a poor goal to concede."
Punditry partner Stiliyan Petrov was wowed by Bodo's number nine Solbakken as he added: "It is Solbakken's play, that's his strength, the creativity, that's what he's been producing.
"They managed to keep him. A lot of clubs have been showing interest in him but they have managed to keep him.
"They let go of players but he is the key player. He is the creativity in the Bodo team and he showed that tonight.
"I think this is the best team, tactically, that's played against them (Celtic this season)."
Petrov praised away boss Kjetil Knutsen's game plan and added: "Bodo/Glimt were prepared for everything. They were well shaped, the positions on the pitch were comfortable for them.
"Celtic didn't create any problems for them because Bodo/Glimt were the team that actually dictated the tempo. They wanted Celtic to play in a certain way and they managed to do that."
