WHEN the time comes for Ronny Deila and Celtic to part ways, the debate on his achievements and shortcomings will likely be both lengthy and heated.

What the Norwegian hopes will not be under similar scrutiny is the manner in which he has comported himself during even the most tense and stressful of moments. Integrity and humility, he believes, are two essential characteristics that define a manager as much as any trophy or title, aspects that should never be compromised regardless of how fraught the situation.

Deila did not come across in any way embarrassed or abashed yesterday despite executing what amounted to a U-turn on the issue of Dedryck Boyata’s red card against Hamilton Academical on Friday night. In the immediate aftermath of the 1-1 draw, Deila felt referee Craig Thomson had made an “okay decision” when he sent off the defender for bringing down Carlton Morris, even though television pictures showed the Belgian had got a nick on the ball first.

It felt almost ground-breaking. Managers admitting that the referee was right and their player was in the wrong tends to happen about as often as Leonardo DiCaprio winning an Oscar. Some, like Arsene Wenger at Arsenal, claim not to have seen an incident at all. Others fudge the issue. Any squad criticism tends to be kept in-house.

Deila, though, simply called it as he saw it, even though he would later change his mind after seeing numerous replays over the weekend. He was criticised for that openness, with Chris Sutton, the former Celtic striker turned acerbic pundit, describing the Norwegian’s actions as “naïve” and “suicidal management”.

Deila conceded that his subsequent change of heart may prove detrimental to Boyata’s appeal to have the red card overturned but there were no regrets over taking such a stance.

"Honesty is one of my values,” he said. “I want to win in an honest way. I don't want to put pressure on the refs and say I don't trust them. I believe in humanity. I believe everyone wants to do their best but you have to admit mistakes.

"I am also a humble guy and when I see something wrong, I will say it. You can't fool the supporters. They see what they see. If I say something that isn't right, they will say, “He’s doing that to protect things and keep a positive tone”.

"I see what I see and I say what I see. I tell my players this, too. We want to be a respected club with good values. That is not about trying to find things to pressure people. Things should be right but I will say when [match officials] do wrong things, like the handball in the semi-final [against Inverness Caledonian Thistle] last year. Everybody could see that was the wrong decision but I want to have a good relationship with the people around us. Players should be humble and honest. That's important.”

Deila was surprised to learn Celtic have been shown 12 red cards during his 18 months in charge but felt that was more for poor challenges than for dissent. “We don’t get those cards because we shout at refs, it’s for tackles,” he added. “We play aggressively and we also play a high line so that means we get caught one versus one playing in their half of the pitch. But we learn through experiences. One of the most important things for any defender is to stay on their feet especially around the 18-yard box when you are alone with a player.”

If the red card was one negative aspect of Celtic’s performance against Hamilton the other night, then another was the penalty missed by Leigh Griffiths. Deila, a defender to trade, revealed he was a regular penalty taker during his playing days in Norway but would now prefer his strikers to step up to the mark. He does not expect Griffiths to shun that responsibility should Celtic win another against Dundee tomorrow night.

“I think Leigh will want to take it if we get another penalty. If you get fouled in Norway we normally give it someone else. Maybe that’s a stupid thing. There are many opinions on these things. But I like strikers to take penalties because we want them to be the top scorers and they are most used to being in this situation. I took penalties and I was a central defender, but now it gives confidence to the strikers and they should be the best in these situations.”

Griffiths had a mixed night from the spot against Hamilton, scoring his first penalty but having his second one saved by goalkeeper Michael McGovern. The striker seemed a bit hesitant as he ran up to his second one and Deila admitted there could be a case for someone else having a go should ever Celtic win two awards in the one game again.

“Yes, maybe that is something to think about. But you have to trust people. Leigh wanted to take it on Friday but maybe he will give the ball away the next time. His second penalty was a little bit high but it was a good save as well.”