RONNY DEILA, the Celtic manager, last night claimed it was ridiculous to suggest John Collins was wrong to highlight the difference between the test his club faced at home compared to European competition.

And the Norwegian manager insisted some people in the game simply couldn’t handle the harsh truth set out by his No.2.

Aberdeen manager Derek McInnes took special umbrage to the comments made by Collins about the other teams in Scotland not being smart enough to challenge the champions, which he labelled disrespectful and even suggested the former Scotland internationalist had “a lot to say for an assistant manager”.

Deila could not believe McInnes and others believed Collins was speaking out of turn and that it was “stupid” to launch a counter-argument.

The point made by Collins was that his own side do not get punished by opponents in the Ladbrokes Premiership as they do at any level in Europe, which ironically was a subject touched on by McInnes recently, something Deila seized upon when asked for his thoughts on the weekend fall-out.

“It is such a stupid thing to discuss," said Deila. “If the coaches in Scotland sat down and discussed this, we would not argue. It would be over after a minute. But because we are making an issue of this, it is just a circus. It is stupid.

“Because everyone knows it is tougher to play in the Champions League than it is to play in the Scottish Premiership. It is also tougher to play in the Champions League than it is to play in the Norwegian League, Swedish League, Danish League or whatever.

“You get tested more defensively in the Champions League and you get punished more for mistakes. That’s not to disrespect Scottish football, it’s just truth.

“We meet the best teams in Europe. I think Derek McInnes agrees – he said that the team they played from Croatia tested them like no other team has done. So I think we all agree. This is creating a conflict that is not there. Of course it is tougher to play in Europe than it is in Scotland.”

Paul Hartley, the Dundee manager, joined in the criticism when he put forward the argument that Celtic's financial strength makes the competition too one-sided.

"I think it's unfair on the rest of the clubs in Scotland," Hartley told Sky Sports. "I think it's being disrespectful. We try our best. We haven't got the budget of every other club and Celtic are way ahead of us but I think, on our day, we have shown we can give them a game.

"They have already taken three players [Dundee United's Gary Mackay-Steven, Stuart Armstrong and Nadir Ciftci] from the Scottish Premiership, so it can't be that bad. They'll probably look at more players. Aberdeen ran Celtic close last year and just fell short. Aberdeen are strong, Hearts are strong."

However, former Motherwell and Rangers manager Stuart McCall said: "In the main, John Collins is only being honest.”

Deila was particularly unhappy with the way his trusted lieutenant was so publicly criticised by McInnes following Aberdeen’s victory over Kilmarnock at Pittodrie on Sunday.

The Norwegian said that if anyone in Scottish football was right to make such comments it is Collins, a man he has the utmost respect for after over a year of working alongside him.

“[McInnes] should call me if he is angry about it,” said Deila. “What I can say is that if anyone calls John Collins disrespectful, then they don’t know John Collins. He is the most respectful guy I ever met in my life. His values are unbelievable.

“You have to be honest and tell it how it is to the fans and everyone else. That’s what newspapers are all about, to give information to the people.

“If it is hard to say that is it harder to play in the Champions League and that you get punished more there than you do in the Scottish league, then McInnes can be as angry as he wants for me; because that is just stupid. It is a truth he said himself about the team from Croatia.”