Shane Duffy is the type of player who would walk 500 miles for Ireland, and then, no doubt, walk 500 more.

The stalwart centre-half is now travelling the width of the European continent - or about 5,000 kilometres - following his battle for fitness, as Ireland take on Georgia in a vital Euro 2020 qualifier in Tbilisi.

Both manager and player were optimistic over the past couple of weeks that Duffy would be fit for some part of this double-header.

So for Duffy to commit to a seven-hour flight, albeit in "a seat with extra leg-room", indicates that the Brighton defender will line-out at the Boris Paichadze Arena on Saturday.

Ireland's defensive dilemma has been very well documented over the past few weeks, starting with Enda Stevens’ suspension, Richard Keogh’s horrific knee injury and Duffy’s battle for fitness, and it looked as if Mick McCarthy would be without three of his four first-choice defenders for the Tbilisi clash.

Keogh’s injury is so serious that he is more or less gone from the McCarthy campaign picture, as he is unlikely to be fit for the tournament next summer should Ireland qualify.

Stevens, of course, comes back into contention for Tuesday – more of that anon – and Duffy’s early return suggests that there will now be two first-choice in the four that will start. A fifty per cent return that the manager will certainly take at this stage.

John Egan is the man mooted to come into the back four in place of Keogh and it is fair to say that the Sheffield United man has been knocking on the door for a starting place since the start of the McCarthy reign.

Kevin Long played alongside Egan in the friendly match with Bulgaria last month and they performed admirably.

On top of that, the two Corkonians appear to have a very good relationship on and off the pitch, and understand each other’s game, which would have put the manager’s mind at ease somewhat over the past couple of weeks.

However, if Duffy is fit, he starts.

The Derry man has established himself as the main man in the middle of defence since Euro 2016, and what the manager needs to do now is to form a new partnership to take him through the next three qualifiers and hopefully on to the Dublin-hosted tournament next summer.

On paper, the Duffy-Egan partnership should work well as both are strong combative defenders, while Egan’s composure will also allow Duffy to concentrate on attacking the ball both at the back and going forward.

Duffy perhaps likes the line a little deeper than Egan is used to, but as the Blades man said during the week, the manager will let them know exactly what he wants in that department ahead of the game and there should be no problems with communication on the pitch.

Seamus Coleman will again captain the team from his trusty right-back position and it looks as though Matt Doherty will get the nod to finally impress the manager, albeit on the left side of defence.

Considering his form at club level, it is remarkable that Doherty has only started one of Ireland’s qualifiers in this campaign.

The Wolves defender was asked to play ahead of Coleman on the right flank away in Gibraltar in the first game and the Dubliner was effectively scape-goated early after the break as Ireland could not dominate the perceived minnows.

There is no doubt that McCarthy would play "The Doc" at right back in Coleman’s absence but it appears that slotting him in at left back is a last resort, after Greg Cunningham picked up a cruciate injury last weekend, ruling him out for the foreseeable future.

Doherty has played on the left before and will look to put his hand up to maintain his place for the Geneva game on Tuesday, yet if things are not going to plan in Tbilisi on Saturday, McCarthy may again call him ashore earlier than planned.

James McClean will be ahead of Doherty on the left flank on Saturday and it is imperative that the two strike up some sort of relationship early in the game.

McClean has no problem putting in the dirty work – quite literally, one might say – and that should allow Doherty the scope to bomb forward when the chance presents itself.

On the right side, Callum Robinson should fill the wide role and again will link up well with Coleman marshalling that side of the pitch.

Ireland’s midfield three picks itself with McCarthy set to name his strongest trio, and not looking ahead to the Switzerland match.

Glenn Whelan will surely be asked to start the game in Georgia, which is arguably the more important on the grander scheme of things, while Conor Hourihane and Jeff Hendrick will make up the three in the middle.

Darren Randolph takes the number one jersey – or the 23 as is his preference – which leaves just the one decision for the manager to ponder.

While Duffy travelled to Georgia, David 'Didzy’ McGoldrick did not make it to Dublin for the flight to Tbilisi, and as a result, the manager needs to name someone to lead the line against Georgia.

Robinson could certainly fill that role on Saturday, which could see Alan Judge deployed to the right side of the three, however, should the Sheffield United man start on the right, it leaves a big call for that striker’s role.

It may come down to a choice between head and heart for the manager who has been giving the nicest possible headache following the week that Aaron Connolly has enjoyed.

The Brighton striker was hauled out of the Under-21 squad following a remarkable brace against Tottenham last Saturday in what was his first Premier League start for his club.

Starting Connolly against Georgia on Saturday would be a gamble in terms of asking a teenager to make his international debut in such a vital away game.

But you get the sense that Connolly would thrive in such circumstances and hit the ground running in that central role as his confidence levels could not be higher.

James Collins, on the other hand, ticks a lot of boxes for what McCarthy is looking for on Saturday; an old-school centre-forward who will create a commotion in the heart of the defence, allowing others to thrive.

Collins put in such a shift against Bulgaria during the time that he was on the pitch, and the fact that he got on the score-sheet is a real bonus in the manager’s eyes.

Scott Hogan and Sean Maguire also offer goalscoring options but most likely in an impact role should Ireland need a goal.

Five victories out of six for Ireland against Georgia in recent years, but never by more than one goal.

Goalscorers aplenty in this Ireland squad – based on club form at least – so the manager will be hoping that he cracks the combination to take all three points to take to Geneva on Tuesday.

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