Ireland 2-1 Bulgaria (4-2 aggregate)
Eoin Harrington reporting from the Aviva Stadium
Assistant coach John O'Shea was impressed by the resilience of Ireland in victory over Bulgaria on Sunday night, as they triumphed 4-2 on aggregate.
For the second game in a row, and the third time under Hallgrímsson, Ireland came from behind to win, on a night that was nervier than the head coach may have wanted in the Aviva Stadium.
After Valentin Andov stunned the Aviva with his point-blank strike after half an hour, there was a tense air about the stadium from the home fans.
However, second-half goals from Evan Ferguson and Adam Idah would turn the game around and ensure Ireland will remain in UEFA Nations League B.
The resilience Ireland have displayed in fighting back from behind under Hallgrímsson is a new trait. It had been over a decade since Ireland came from behind to win before the win in Helsinki - they've now done it thrice in six months.

23 March 2025; Adam Idah of Republic of Ireland shoots to score his side's second goal during the UEFA Nations League B/C Play-off 2nd Leg match between Republic of Ireland and Bulgaria at the Aviva Stadium in Dublin. Photo by Ben McShane/Sportsfile
It is a distinct change since Hallgrímsson took over. Addressing the Irish media after the game, assistant head coach John O'Shea was asked whether the newfound resilience of this Ireland team reminded him of the sides he played on.
Yeah, listen, you need that resilience if you're going to qualify for major tournaments.
But also, we want to make sure we're taking advantage of that resilience in a sense of when you start so well in games that you wanna be taking the lead in the game.
Yeah, it's great to come back and we've done it now. It's not easy to do in international football [to] come back from behind, whether it's away from home or home itself.
Listen, we know we have to be winning these games in the sense of, ultimately, a group B team against a group C team.
When you go about it the way we did, when you have that character to dust ourselves down, reset, go and get our chances and win the game.
There were a few changes to the Ireland team from the first-leg win in Plovdiv last Thursday, and O'Shea explained the rationale behind the coaching team's decisions.
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John O'Shea praises Ireland resilience in comeback win v Bulgaria
Evan Ferguson was brought back into the starting XI for Sunday night's second leg and was expected to partner Troy Parrott up front as he did in Athens last October.
However, the West Ham striker regularly found himself dropping unexpectedly deep to pick up the ball and it was only when he moved further up the pitch after half time that he was fully able to impact the attacking play.
O'Shea said he and the coaching team had been satisfied by Ferguson's display, and also said he hoped his goal would reinvigorate him after a tough few months at club level.
The most important thing is that we have a healthy Evan Ferguson, a fitter Evan Ferguson each camp that goes by and hopefully that will be the case.
Obviously West Ham know him, the manager knows him very well. Hopefully they're getting a much happier Evan Ferguson in that sense going back with minutes in the tank and with a goal as well.
Really pleasing for us but I'm sure West Ham will get the benefit of that too, and that leads to us getting more benefit in the summer going forward and seeing what happens.
O'Shea also praised the performance of Finn Azaz, who was once again the conductor of Ireland's attack in his second superb performance of the week.
He pointed out that Ireland are steadily building up some depth in attacking areas as their young players develop.
"The good thing is the options, in the sense of that attacking [unit]," O'Shea said.
"Whether in some games you're going with two more direct strikers, or whether you're going with a classic 10 and a 9, that option.
"I think Finn [Azaz] is showing he's more than capable to adjust as well. He can connect, whether it be two strikers or a himself and a 9 as well.
"Michael Carrick has used him at Middlesbrough all the way across, in behind the striker, whether it's on the left-side, right-side, in that central position too. He's definitely shown his most exciting form in that 10 role."
It may have been nervy but it's job done and all eyes on the World Cup qualifiers for Ireland now.