Hanley stood firm as the bar wobbled

As Scotland’s crossbar rattled, stung into life by Grant Hanley’s wayward injury-time header, the Tartan Army was rattled too.

For 90 minutes, they had basked in the light of a much improved defensive performance from Hanley and central defensive partner, Russell Martin.

Everything Ireland launched at them, from Shane Long’s scampering forward forays and Jon Walters’ battering ram physicality to Aiden McGeady’s desperate trickery, was dealt with in relative comfort.

Then came Hanley’s header and it was mighty close. Too close for comfort.

In the south-east corner of Celtic Park, 4,000 pairs of Irish hands flew to 4,000 Irish heads. “Oh me nerves!” declared one of the fans’ flags. That summed it up perfectly.

Hanley and Martin’s partnership at the heart of the defence has frequently tested the Tartan Army’s composure.

Cheap goals have been conceded, points lost but Gordon Strachan has persisted.

The theory goes by maintaining the pairing, allowing them to form an understanding, Scotland’s defence will get stronger. Against the Republic, the evidence suggested the theory is credible.

Walters and Long, Ireland’s little-and-large strikeforce, are hardly world-beaters. That much is obvious.

They are, however, Premier League players and better than anything Martin and Hanley face on a week-to-week basis.

If that knowledge was enough to trouble the Tartan Army before kick-off, however, it quickly became apparent there was little need for concern.

From the off, Hanley and Martin had the better of their opponents, each outpacing Walters and outthinking Long with regularity.

Yes, Hanley might have seen red rather than yellow for his early challenge on Long.

But by the time Long lashed out at Hanley five minutes before half-time, tripping him in a nothing area of the park, it became apparent the Irish were losing the battle.

When Long was withdrawn with 22 minutes to go, it was tantamount to an admission of failure.

Hanley and Martin had shut down their opponents. The onus was on Scotland’s attackers to capitalise.

Six minutes later, they did just that and all that remained was to hold out.

With 55,000 fans peeking through their fingers at Celtic Park and countless more watching at home the pressure was palpable, but Hanley and Martin, now with Robbie Keane to think about, did their jobs and Scotland profited.

It almost went terribly wrong at the death, but in football, “almost” is nothing.

The crossbar was rattled, but the net did not bulge, and Scotland, with Hanley and Martin at the heart of defence, kept a clean sheet.

That’s progress.