The Celtic midfielder Kris Commons has pointed the finger at his team-mate Efe Ambrose following Tuesday's 3-0 defeat by Juventus in the first leg of their Champions League last-16 tie.
Ambrose, the Nigeria defender, only arrived back in Glasgow on the morning of the match after the Africa Cup of Nations, but was included by Neil Lennon in Celtic's starting lineup after insisting he felt fit to play.
Ambrose gifted Alessandro Matri an early goal, missed Celtic's best chance of the night when he sent a free header straight at Gianluigi Buffon from six yards and then lost possession to allow Mirko Vucinic to claim a late third and virtually send Juventus into the Champions League quarter-finals.
Lennon must be rueing his decision to pick Ambrose but Commons believes the player is responsible. Commons said: "Look, the manager picked him. The manager pulled him to one side and asked him if he was feeling OK. He said he was feeling brilliant. If he wasn't feeling OK then he should have said so. If he felt good then he should have put in a better performance."
Victor Wanyama also missed a good headed chance while Commons had a series of efforts on goal as Celtic created a number of other half-chances, especially in the first half.
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. The referee Alberto Undiano Mallenco twice took action, but only to hand out yellow cards to players from each side.
Commons told BBC Scotland: "Gary Hooper was pulled down to the ground on far too many occasions and we got no rewards. 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."