But Celtic manager
Lennon must be rueing his decision to pick Ambrose but Commons believes the player is responsible.
Commons told several British newspapers: "Look, the manager picked him. The manager pulled him to one side and asked him if he was feeling okay. He said he was feeling brilliant.
"If he wasn't feeling okay then he should have said so.
"If he felt good then he should have put in a better performance."
But its trip to
Commons said: "It was just very sloppy individual mistakes – something you'd probably get away with on a playground, not in the last 16 of the Champions League.
"There are certain individuals who let the team down.
"Hopefully this is just a one-off. The back four have made errors which have probably cost us the tie. But it's partly down to them why we're here in the first place.
"It's just a bitter one to swallow."
Commons also pointed the finger at the Spanish officials over their failure to punish some extra-tight marking as Juventus defended set-pieces.
Referee Alberto Undiano Mallenco twice took action – but only to hand out yellow cards to players from each side.
Commons told BBC Scotland: "
"You've got a referee there, a guy behind the goal, a linesman – the whole idea of the official behind the goal is to look out for this sort of stuff.
"If he can't identify when people are being hauled, manhandled, wrestled to the floor, then I don't think he should be in a job.
"He's 10 or 15 yards away and if it was a clear foul, it should have been a penalty.
"He said if you do it again they'll get a penalty – that was in the first half.
"He kept stopping it and booking people and telling people to stop it.
"It clearly had no effect because right up until the 91st minute when we had a corner, it was still going on."