This is the day of truth for Ireland's tournament ambitions. The splendour of the second-half performance of the Cameroon game leaves us in firm control of our destiny as we prepare for the pivotal game of the group stage.

Gary Breen's injury is unfortunate for the player, but just clarifies the picture at the back for me. Kenny Cunningham will enhance the central defensive equation in a back four along side Steve Finnan, Stan Staunton and Ian Harte. I would restore Jason McAteer to the right side of midfield, with Kilbane again on the left. No need to tinker with Damien Duff and Robbie Keane; they have the skill and understanding to torment a German defence that is susceptible to imagination and speed.

Another draw is the most likely outcome. Obviously defeat doesn't come into the reckoning for Ireland - it would scupper our chances of progression. Even if we secure a draw today, it still may not be enough. I believe that Germany are due a sub-standard performance soon, and hopefully that will come against us. But they are more likely to be exposed by Cameroon and I remain faithful to my prediction that the African champions and Germany will advance.

But it will be a close-run thing. What Ireland have demonstrated is their potential to score. I'm really looking forward to watching Duff run at the German defence. He is the key, and he should be located deeper than Keane, in the central area occupied by Dieter Hamaan, whom he should be able to skin.

Keane has rediscovered the requisite arrogance that all born strikers have and he can play off Duff. But more crucially, Duff will give the Irish midfield someone to offer some sort of respite.

I am still awestruck by the degree with which Ireland turned things around in the Cameroon game. Over the first half, they were shackled in a way I had rarely seen an Irish team. Okay, we may not have expected free-flowing football, but Ireland at least harried and got at teams and were never any great respecters of reputation. But they were definitely tethered mentally over the first half. So Mick McCarthy's positive adjustments are laudable and we were unlucky not to have won.

And encouragingly, I don't think Ireland peaked in any way over that closing 45 minutes. They ought not to have many problems in mirroring that type of bravery today because our consistency has always been a strong point. We need another immense contribution from Matt Holland and Mark Kinsella.

We have harped on enough about the traditional Germanic values, but what they also have is a strong midfield. Against Saudi Arabia, they were very impressive in the angles they ran, the way they interchanged and in their discipline. That they were playing very limited opposition should not be over-stated. They are disciplined and well-drilled and effective. I doubt their score of 8-0 will be matched in this tournament.

So it is a monumental challenge but one which the Irish team will undoubtedly fancy now. They will be a lot more free-spirited and confident today. The important thing is that they maintain their structure. Kilbane, even when he isn't playing all that well, gets through an ocean of work and sits nicely in front of Ian Harte, offering that added cover. McAteer will do likewise for Finnan.

We were exposed centrally once or twice by Patrick Mboma against Cameroon, and Cunningham's presence would lessen the likelihood of a repeat of that. The most crucial thing is that we seek to involve Duff as early and often as possible. That is one of the reasons I am against playing him on the wing. It confines him. Our designs are much better served by giving him free reign. Remember how panic-stricken the Germans were by Michael Owen's forays from deep - although their defence has improved.

We shouldn't have reason for complaint if we manage a 1-1 draw. After that, we can only make sure we beat Saudi Arabia and take our chances. With a bit of luck, it will be enough to see us through. It would be harsh to go through the group unbeaten and still not advance, but that may be the reality for us.

Still, this occasion will be memorable. A win is not beyond us, but the Germans are just incredibly tough to wear down to that extent. They also have a strike force that can cause us some problems.

A score draw then, followed by some maths and anxious days ahead. At last we will find out if there is any truth in the luck of the Irish theory.

In an interview with Keith Duggan