Muzzling The Great Dane
With only seconds left on the clock in Cardiff, there was little chance that David Meyler was going to pull out of the challenge with Wayne Hennessy that resulted in his suspension for this crucial play-off first leg in Copenhagen.
His absence will largely shape our approach to tomorrow's game.
Meyler's mobility and ball-winning ability allows O'Neill to play him as the sole defensive midfielder but more importantly it permits the team to press the opposition in a way that just isn't possible with his expected replacement Glenn Whelan. O'Neill has taken Whelan out of his team for two crucial games in his tenure: Italy in the Euros and Serbia in Dublin. On both occasions it was following insipid displays where Ireland had played ridiculously deep and not engaged with the Belgians and Georgians respectively.
And on both occasions his absence saw Ireland play further up the pitch and press aggressively.
The above, and the fact that Denmark's best player operates in his zone, means that O'Neill will almost certainly play with a 'double pivot' with Harry Arter manning the space to his left.
Well that is, if indeed, O'Neill details him to do that.
It was very worrying in Cardiff that neither of the more offensive of our midfielders, Hendrick or Arter, were tasked with closing down Joe Allen. Luckily his exit meant that his influence on the game never grew to a level that would have impacted the match significantly, but for the 37 mins he spent on the pitch he was afforded far too much space.
Arter needs to show a different type of positional awareness tomorrow night.
Worryingly, the last time he and Whelan played together, the Tbilisi debacle, Arter was arguably the worst player on the pitch.
Arise King Arter
Denmark have adopted a pretty direct style of play under Age Hareide (which we've detailed here). Unless they have second thoughts based on how little Wales troubled us with a direct approach, more of the same can be expected against us.
The difference we can expect is that rather than playing long balls down onto Shane Duffy's gleeful head, the Danes will most likely play diagonals to Cornelius or Poulsen (6'3 and 6'4 respectively) on the right wing with a view to Eriksen pouncing on the breaking ball and getting into dangerous positions in front of our back four
Some have raised the idea of man marking Eriksen.
No, just no.
O'Neill will most likely seek to defend his threat zonally, mainly by ensuring the space between our lines is kept to an absolute minimum. This will unfortunately have ramifications on our attacking play.
Denmark's more direct style appears to be geared just towards that. Rather than Eriksen pulling the strings like a Joe Allen, it seems that Denmark look to use him more like an Aaron Ramsey. That he gets on the ball in more dangerous positions closer to goal.
The space that Denmark will seek to release Eriksen into is between our back four and midfield.
As well as McClean helping out Ward, Arter will be key to limited this threat. His play on the ground, scampering and hustling is where he is at his strongest. Defending that channel in front of Ciarán Clark, most especially when Eriksen steps into it, and the knock downs from the right wingers, will be absolutely crucial for us.
Thomas Delaney is the midfielder the Danes will look to instigate the play for them. It will be Hendrick who is tasked with closing down his space and limiting him hitting his dangerous left foot passes.
This might all sound very very negative but given our defensive record in the qualifiers, our available personnel and the extremely impressive defensive shape we showed in Cardiff, it is understandable to expect O'Neill will be confident of being able to deal with the Danish attacks.
Who To Lead The Line?
This very obviously has major implications with how we seek to play when in possession.
Don't be surprised if our passing stats are worse than the 211 attempted passes against the Welsh.
The only real selection dilemma O'Neill will most likely face is who to play up front.
Shane Long's last away start for us was in Tbilisi where he hustled forlornly up front, with a monstrous gap between him and the midfielders. As is often the case, balls ricocheted off his body. Nothing stuck and no midfielders got up in support of him, until far too late in the game.
We've spoken before about Long's poor back-to-goal play. Murphy is far superior at winning aerial balls, offering a presence up front and also at linking the play.
The flip side is he offers no threat in behind the opposition defence and allows them to play a much higher line than if Long was to play.
Long is also much better at pressing as well as offering a threat down the channels.
But such is his well publicised issues in front of goal, it is very difficult to imagine O'Neill starting Long up front.
Long has never been dropped by O'Neill (although he has been moved to the right wing) but it would be a surprise if that wasn't the case this time round.
Murphy played 92 mins in Cardiff (to be replaced by the other Long, Kevin), as O'Neill was reluctant to throw in Maguire or Hogan. However, now that Shane Long is available, we should expect him to at least play the final 20 mins in Copenhagen.
And what a night it would be for him to emerge from his goalscoring depression.
The argument in favour of Long starting (in addition to the above) is that 3 of the 8 goals Denmark conceded in the qualification campaign were from through balls or passes over the top. While they conceded a sum total of zero goals from crosses where a Brady/Murphy combination would be expected to yield chances.
But bottom line, if we do play containment football, let's hope it resembles our performances in the victories over Germany and Wales and not our pathetic attempts in Bordeaux and Tbilisi.
But above all, tomorrow night is about staying in the tie for the 2nd leg.