1. What formation will Ireland adopt?

For much of the Trapattoni regime, many fans and critics lamented the manager’s near-constant use of 4-4-2.

The Italian’s rigid reliance of this unremarkable formation was seen by some as evidence that he was unwilling to change his rigid, old ways and adapt to modern football.

However, Martin O’Neill hasn’t exactly shied away from this style since taking over — while he started with 4-5-1 in his first match in charge against Latvia, he chose to adopt 4-4-2 against Poland.

And who’s to say 4-4-2 can’t be a success for Ireland? In the Premier League, both Tottenham and Man City have this season shown it can still work very effectively when applied properly, even in the ultra-sophisticated world of modern football.

Moreover, there is a dilemma with 4-5-1 in that it would conceivably mean dropping Ireland’s all-time leading goalscorer Robbie Keane — Shane Long would surely be the better option as a lone frontman, given that the LA Galaxy man has struggled on the rare occasions he played there before.

That said, arguably Ireland’s most creative player, Wes Hoolahan, prefers playing in the number 10 role, so the team would surely need to adopt 4-5-1 to get the best use of the Norwich man.

It will therefore be interesting to see which system O’Neill favours tomorrow night, and how the players respond to his instructions.

2. Can James McCarthy and Seamus Coleman reproduce their Everton form?

While not playing badly, James McCarthy and Seamus Coleman have seldom shown the type of form that has won them plaudits for Everton when turning out for Ireland.

Unsurprisingly, there were few instances of Coleman’s customary marauding runs forward in an Ireland jersey while the inveterately pragmatic Trap was in charge.

That should change under O’Neill, as Coleman is one of Ireland’s best attacking options and it would be a shame to see him restricted to defensive duties.

If O’Neill is eager to err on the side of caution, which will surely be required in the upcoming Euro qualifiers against Germany at least, rather than limiting Coleman’s license to get forward, he could play him on the right hand side of midfield. It is not an area in which Ireland are particularly blessed with options as it is, and Coleman’s defensive instincts would provide solid cover, which could prove invaluable when they do meet vastly superior opposition.

Alternately, McCarthy and one of Whelan or Gibson (when he returns) could play a similar role to McCarthy and Barry at Everton, in which the duo sit in midfield, thereby giving the full-backs greater scope to get forward.

The Scottish-born midfielder had a few too many quiet games under Trap, though fans will hope that the tutelage of both Roberto Martinez and former midfield great Roy Keane will enable him to dominate games more frequently than in the past.

3. Will Darren Randolph be given a chance?

©INPHO / Donall Farmer ©INPHO / Donall Farmer / Donall Farmer

Along with Shay Given, Darren Randolph is undoubtedly the in-form Irish goalkeeper at the moment.

He has impressed significantly since his move to Birmingham in the summer, winning their Player of the Month award in August.

David Forde has mostly served Ireland well since being a chance to play as the number 1, but has missed a considerable potion of the season through injury.

Keiren Westwood, meanwhile, is currently injured but is unlikely to get first-team football when he returns, while Rob Elliot is untested at the top level and recent call-up Brian Murphy is also lacking regular game time with QPR in the Championship.

In addition, Forde is 34 and at the very least, Ireland need viable cover in the position. Yet Randolph is inexperienced with just two caps so far, and was ignored completely when Noel King picked his final squad for the Poland and Latvia games.

Surely therefore, Wednesday is the perfect occasion to try Randolph out, rather than sticking with the tried and trusted Forde.

4. Can Ireland combat Matic and co?

Despite not qualifying for the World Cup, Serbia have a number of top players in their squad.

Branislav Ivanovic,  Aleksandar Kolarov and Nemanja Matic could all feature at the Aviva tomorrow, though both Matija Nastasic and Borussia Dortmund’s Neven Subotic have been ruled out through injury.

Ireland will need to keep a watchful eye on full-back Kolarov’s overlapping runs on the wings, while anyone who saw Matic’s accomplished performance in Chelsea’s impressive recent Premier League win over Manchester City will know all about the threat he poses.

Elsewhere, Ireland will also need to closely mark CSKA Moscow’s Zoran Tosic — the former Manchester United left winger already has 53 caps at 26, and is particularly proficient from set pieces.

5. Will the O’Neill-Keane factor continue to pull in big crowds?

There is no doubt that Martin O’Neill and Roy Keane have rejuvenated interest in the national team, after it previously flagged owing to a series of stale performances and Trap’s unadventurous tactics.

37,100 people was the official attendance for the Latvia friendly back in November, and it’s doubtful that even half that many people would have shown up had the Italian still been in charge.

Yet now that the dust has settled and people are beginning to get used to the O’Neill-Keane combo, will a palpable air of excitement still prevail and are fans still going to turn up in large numbers given that the novelty has more or less worn off?

The fact that it’s been four months since Ireland’s last home friendly, while it’s nearly three months until their next game at the Aviva against Turkey, suggests there should be a decent attendance, while provided the team perform as convincingly as they did against the Latvians, then the atmosphere should be similarly impressive.

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