THAT Ange Postecoglou believes attack is the best form of defence is self-evident from his approach so far as Celtic manager, but there appears to be method behind what has often appeared madness during these early, wildly entertaining weeks of his tenure.

The six-goal drubbings of Dundee and St Mirren amid the goal glut over the last month or so have displayed the attacking prowess that Celtic now enjoy, but less noted has been the four clean sheets garnered from the last five matches.

Yes, Postecoglou’s side have given up chances in all of those games, and benefitted from an erroneous offside call against St Mirren, but the stats suggest at least that his aggressive front-foot style doesn’t necessarily equate to leaving the back door wide open.

It is no surprise then to hear Postecoglou talking bullishly as he takes his team to The Netherlands for perhaps their sternest examination yet against AZ Alkmaar. The rope-a-dope will not be adopted as Celtic go to build upon their 2-0 lead from the first leg in Glasgow, not to protect it.

“You can’t go there and just try to defend for 90 minutes,” Postecoglou said.

“As I said after the first leg, they are a good side and being at home they are going to take the game to us. If we were to go there and sit back for 90 minutes, you are sort of more hoping you get through.

“What we know is that if we play our football, we are always threatening going forward. And if we score goals, it puts more pressure on them.

“So we won’t change our approach. We’ll go there and try to play our game and impose our style. If we do that, it gives us a better opportunity to be successful.”

Part of Postecoglou’s philosophy is that the concept of separate defensive and attacking components of his team is an alien one. The whole must function together for either part of their game to succeed.

“I don’t separate them like that,” he said.

“I think the fact we are scoring a lot of goals is because the back four and Joe (Hart) are continually looking to play out from the back, which gives us more opportunities.

“So they are part of that goalscoring threat and defensively the whole team is working hard to deny the opposition opportunities.

“It doesn’t fall to one line for one or the other. The strikers scoring goals get the headlines, but internally the players are well aware that is something that begins from playing from the back and our goalkeeper being brave enough to start all of that with the ball.

“Defensively, we have been sound, but we still have to improve all areas, every unit.

“But I haven’t felt in any game we have been under siege or under pressure and looking like conceding a lot of goals.”

Many outside of Celtic, and perhaps among their support, will view the next few days as the acid test of where Postecoglou’s team currently are. The run of home wins was most enjoyable for them of course, but there is a feeling that away matches to Alkmaar and Rangers will be a more accurate gauge of their capabilities.

So, the match in The Netherlands this evening is significant for many reasons, with Postecoglou eyeing the reward of more big European nights at Celtic Park.

“More importantly, it’s important for the club,” he said. “It’s something that helps us in terms of building something for this year.

“We obviously missed out on the Champions League which was disappointing, so this is a chance to set ourselves up to get a group stage in the Europa League and we know there are going to be some big games in there.

“So for a whole lot of reasons, it's an important fixture for us and the players and all of us are looking forward to it.

“It can set up big nights for both the players and the supporters. That’s why you want to be in Europe, you want to play against some of the other big clubs on the continent and the Europa League group stage gives you that.”

So, the whirlwind introduction to life at Celtic continues for Postecoglou, with barely a week going by so far without a season-defining match or two thrown in. Not that he would have it any other way.

“To be fair, they've all felt like big weeks since it started,” he said. “The first week was a Champions League game.

“So I understand that when I took on this role that is the club I’m at where every game is a big one.

“Whether that is Europe, league game, cup game. I love that. That’s why I am here.

“But yeah they are two massive games [against Alkmaar and Rangers]. Two high-profile games and I’m aware I’m exactly where I want to be and that is right in the middle of it.

"I’m looking forward to it immensely.”