ON THE HOUR mark of Friday night’s fog-affected Bosnia-Ireland Euro 2016 play-off first-leg, Martin O’Neill made a substitution that would significantly influence the subsequent half hour, as well as this evening’s forthcoming encounter.

Although clear-cut chances had been few and far between, and the Irish team for the most part looked relatively solid, the Bosnians had clearly identified the Boys in Green’s left-hand side as a weakness.

Ireland’s problematic left-hand side

In the first-half, Bosnia right-back Mensur Mujdža (Freiburg) and right-winger Edin Višća (İstanbul Başakşehir) continually exposed Stephen Ward, and Robbie Brady ahead of him.

Ward looked nervy all night and made some poor decisions, though it’s easy to sympathise with him to an extent, as the 30-year-old Burnley player has played just 12 minutes in the league with his club, in addition to making one Capital One Cup appearance.

Ireland’s left-back wasn’t always helped by Brady, who tended to be lax in possession and at times did not provide his teammate with adequate cover

Mujdža gave a sign of what was to come on 10 minutes, getting the better of Brady, before delivering to Miralem Pjanić (Roma), who blazed his shot well over the bar.

Three minutes later, Višća, for the first but by no means last time found space on the right to deliver a cross in, with Ciaran Clark needing to be alert to clear the danger.

Bosnia’s right side was a problem all night, and it wasn’t just Mujdža and Višća who caused chaos. In the clip below, Vedad Ibišević (Hertha) robs Brady of possession and Bosnia launch a counter-attack, ending with Senad Lulić (Lazio) making an incisive run through on goal and unsuccessfully attempting to win a penalty.

In the clip below, Brady again loses possession, but Ibišević can only find the side-netting from Višća’s cross.

An awkward situation became even more perilous on 26 minutes, when Stephen Ward was booked for a cynical pull-back on the increasingly influential Višća.

After 28 minutes, Višća was again involved, linking up with Edin Džeko, with the latter’s cross stopped by a timely interception from Seamus Coleman.

The speedy winger Višća was released down the wing again shortly thereafter, but Zukanovic’s ensuing header from his teammate’s cross was straight at Darren Randolph.

Bosnia’s failure to fully capitalise on their superiority in this area of the field could be attributed to a mixture of inept finishing, strong Irish defending and, as we see below, poor delivery (though Mujdža wasn’t helped by an unfortunately timed bobble).

Despite Ireland’s obvious defensive issues, the teams went in at the break with the score at 0-0. The right side had been the Bosnians’ one clear area of joy, with the hosts otherwise struggling to create much of note, and the Irish for the most part coping comfortably with long balls played up to strike duo Džeko and Ibišević.

It was telling that Bosnia’s first genuinely clear-cut chance, early in the second half, came about as a result of an Irish mistake rather than the home side’s own ingenuity. Jeff Hendrick’s clearance ricocheted off Džeko and fell kindly to Lulić, but Randolph got down well to save smartly.

On 60 minutes, Martin O’Neill made the substitution that changed the match entirely. James McClean replaced the ineffectual and isolated Wes Hoolahan, with the Derry native slotting in to the left-wing position and allowing Brady to move into a more attacking role just behind lone striker Daryl Murphy.

O’Neil’s ongoing experimentation with different number 10s

Martin O’Neill has experimented with the number 10 position ever since Ireland’s first match of the Euro 2016 qualifying campaign against Georgia.

Back in September 2014, with Aiden McGeady having started the match more or less as an orthodox left winger, in the final 14 minutes, Robbie Brady was introduced to play on the left flank. The change allowed McGeady to go behind the striker, as Ireland went in desperate search of a winner in Tblisi.

O’Neill’s substitution paid off in injury time, as McGeady scored a spectacular winner to hand Ireland all three points (see video above). Following this exquisite attacking high point, the Boys in Green haven’t scored twice in a competitive international, excluding games against Gibraltar, since then.

Given these late heroics, it was no surprise that for Ireland’s next big game (let’s overlook the 7-0 hammering over Gibraltar in Dublin) away to Germany, McGeady started in the number 10 position behind Robbie Keane. But with the Scottish-born winger struggling to have an impact on the match, Wes Hoolahan was introduced on 76 minutes and positioned behind the striker. McGeady, meanwhile, moved to a more familiar left-wing role, and the team performed considerably better as a result. The Everton outcast has seldom featured for Ireland since, though he did come off the bench to play at number 10 for the dying minutes of last Friday’s match.

And since the disappointing 1-0 loss to Scotland at Celtic Park — a rare instance during this campaign of Ireland playing a pretty straightforward 4-4-2 perhaps owing partially to Hoolahan’s unavailability through injury — the Norwich playmaker has been trusted fairly regularly in the number 10 position.

The substitution that changed the game

On Friday night, with little going right for the isolated Hoolahan, Brady was given an opportunity to play behind the striker and duly grasped his chance with a superb goal.

Yet placing Brady centrally was not the only important element of O’Neill’s substitution. Bringing James McClean on was also key. O’Neill gave McClean his debut as a youngster at Sunderland, and his introduction to proceedings on Friday clearly made a difference. It gave Ireland some much-needed energy down the flanks, with McClean also being one of the few players in the squad capable of carrying the ball and taking on defenders — his impressive pace and power contrasting with Brady’s more subtle qualities.

After 67 minutes, O’Neill also brought on Marc Wilson for the tiring Ward, who had continued to be exposed down Bosnia’s right in the early parts of the second half, and came close to picking up a second booking for another rash challenge.

These changes were implemented conceivably to make Ireland defensively stronger on their left-hand side, so it was ironic that Bosnia’s goal again emanated from this flank.

Surprisingly, Bosnia’s right side had been altered completely by the time they equalised on 85 minutes. Mujdža, so effective in the first half, had to come off after just six minutes of the second period, having picked up an injury. More surprisingly given that he had been probably Bosnia’s man-of-the-match up to that point, Višća was sacrificed with 17 minutes remaining, in order to accommodate a third striker, Milan Đurić (Cesena), whose arrival prompted Ibišević’s shift to the right.

After Ireland had secured an unlikely lead, Lulić played through substitute right-back Ognjen Vranješ (Gaziantepspor), who had taken advantage of a lapse in concentration from James McClean, and Džeko made no mistake with a simple finish from close range after the defender’s pinpoint cross.

So just as O’Neill’s substitution had directly impacted on Ireland’s goal, it also played a big part in Bosnia’s equaliser, with McClean culpable to a degree, while Džeko showed excellent movement to evade Richard Keogh, who was magnificent on the night apart from that one blip.

What significance does it all have in the context of tonight’s game?

One of the few issues that was clear from Friday’s fog-affected clash was Bosnia’s superiority down their right-hand side.

Whether it was Mujdža and Višća, or Vranješ and Ibišević, the Bosnians posed a conspicuous threat to Ireland’s vulnerable left flank.

Despite coming away from Zenica with an encouraging 1-1 result, O’Neill will know Ireland cannot risk affording the aforementioned Bosnian players so much room to play this evening.

Yet combating the issue is easier said than done. O’Neill has a number of options at his disposal, though none of them look entirely risk-free.

Does he place faith in Ward despite his lack of match sharpness, or bring in the Marc Wilson, who also lacks game time of late (or even someone entirely different such as John O’Shea, who could still potentially return from injury tonight)?

On the left wing, the Ireland boss could opt for Robbie Brady, who is fantastic going forward, but at times looked ill-disciplined and defensively vulnerable in the first leg. Or does he start with James McClean, who provided the team with greater solidity for the most part, but also was primarily responsible for the concession of Bosnia’s equaliser?

And if O’Neill picks McClean, does that mean starting as Ireland almost finished with Brady at number 10 following his superb strike? Alternatively, does he keep faith with Wes Hoolahan, who has been fantastic for much of the campaign, but whose fitness issues have been well documented, behind the striker?

Whatever happens tonight, you get the sense that Martin O’Neill, with the many tight and potentially game-changing decisions he has to make, will have to go some way towards justifying his lucrative salary if Ireland are to progress.

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