Dundee boss John Brown blamed assistant referee Andrew McWilliam for denying his side a Scottish Cup replay as they suffered a 2-1 defeat to Dundee United.
Brown claimed McWilliam failed to flag for a throw-in as Gary Mackay-Steven had run the ball out of play on the right wing before Brian McLean headed home Dundee United's first goal in the Dens Park win.
Dundee appealed but the assistant referee did not agree, and although Dundee equalised through Jim McAlister, Mackay-Steven drilled the winner in the 35th minute.
A frustrated Brown said: "I'm pretty bitter about a decision that never went our way, a clear throw-in, that ultimately results in a free-kick that shouldn't have happened.
"I don't really need to talk about how you defend it because that shouldn't come into play if they do their jobs right.
"An official has cost this football club a replay and a chance to get to a semi-final.
"That decision in the first half basically took it out of our hands."
Brown said he spoke to the Scottish Football Association observer, former referee Bob Valentine, after the game.
He said: "The referee supervisor came out and said the ball was out. It's human error but it's a sore one to take.
"I'm 10 yards away and he's right there. How he can't see that.
"I don't want to be throwing it all on the official but that one decision - you need them to be on their game, they don't do it right and it has cost us the game.
"Take that away and it was an even game. But I wish United all the best."
Ambrose only arrived back in Glasgow on the morning of the match as Celtic went down 3-0 at home in the first leg of their UEFA Champions League clash last month, having been away at the Africa Cup of Nations.
Commons felt Ambrose should take some blame for the disappointing result, saying: "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."
Ambrose insists there is no problem between the pair and has instead used Commons' remarks as motivation to improve and never repeat the same mistakes.
"Kris is a great friend. We've been chatting and laughing," said the defender in the Daily Record.
"But I know how he felt after the Juve game. Sometimes when you lose it brings out another side of you.
"I know when I don't feel happy about something, it's good to say so. I understand that and just take everything the way it comes - and Kris has since apologised.
"However, he did not express things in the proper way. If Kris had been calm when he spoke, he wouldn't have said what he said. But I understand.
"What he did do was make me a better player and gave me a challenge. Next time I will stand up for myself and stand up for the team. That's what he was telling me.
"I know what he was saying better than people who were not in the dressing-room."
Ambrose stands by his decision to declare himself fit and is now just focused on helping Celtic bounce back ahead of the return leg in Turin on Wednesday.
He said: "You learn from your mistakes and I think I have learned from mine and put it behind me. The most important thing is what lies ahead for us - not what's in the past.
"At the first goal, I didn't lose the flight of the ball. The Juventus striker was clever and gave me a push to unbalance me.
"Their strikers were good but we would have kept them out if it hadn't been for our mistakes.
"I don't regret playing in that match. I came to the club to do a job, which is to play and help my team. I like working hard and playing. I love my job.
"I want to have something to do, to help my team. I love my club and they needed me to help them qualify.
"It didn't work out the way it was supposed to though, or you would not be asking me these questions. If we had won, you would not be asking me this.
"You would be telling me it was a great thing, coming back to help my team win.
"Football is like this and you have to deal with the bad moments."
