The Nigerian defender was personally culpable for the goals scored by Fenerbahce in the Europa League tie at Parkhead 16 days ago, which allowed the Turks to recover from being 2-0 down to snatch a draw. Unfortunately, the lack of concentration in evidence on that occasion was hardly unprecedented. Indeed, there were echoes of previous costly errors against Juventus and Legia Warsaw.
With the first leg of a double-header against FK Molde in Norway looming on Thursday, those Celtic supporters accustomed to referring to the 26-year-old as Iffy Ambrose may be fearing the worst. However, the player insists that he has changed.
Following imprecations from manager Ronny Deila and his coaching staff, Ambrose has vowed to become more effective by playing less football.
“Last season the gaffer told me that I was trying to take too many risks in my games so they have tried to make me a different player,” he explained.
“I don’t do that any more, I try to play simple and to just defend. I think I am getting better and I work hard every day to make sure.
“The first season after the gaffer came was difficult for me. But when he sat down and spoke with me I started to realise what he was trying to do.
“In the past I didn’t always know what my mistake had been but he had seen them and called me on them and he and my team-mates will help me so, for me, that is a positive thing.
“Once you try to learn then you will play better. So now I need to play simple football and try to move the ball more quickly because that is what the gaffer wants me to do.
“It’s good for me if I try to play less football and not take too many touches.”
Meanwhile, Ambrose has prophesied that he will atone for his previous sins in one or more of the forthcoming matches against Molde, Aberdeen or Hearts [in the League Cup at Tynecastle].
“It was good, after the Fenerbahce game, to hear the manager say that he trusted me,” he explained. “He and [coach] John Kennedy have really helped me.
“When you have a manager like that it means a lot. So what else can I do but give everything to this team?
“I owe this team and I know that, a couple of games ahead, there is a way I can pay them back for all of this.
“There is a way I can help them and that is a positive thing I am looking forward to. You can never know when Efe Ambrose is going to do his somersault!
“When there is a game when Celtic really need a goal… you neverknow. Of course there will be a big moment.
“I can never promise how many somersault moments there will be but I want to give something back and I know that that game is coming soon.”