The politics of succession are delicate: how many veterans can you cull in one go? An experienced player who loses his place to a younger rival is unlikely to forget or forgive; 15 years later he’ll probably still be doing bitter interviews about how your training sessions were basic and the step-up to international level was too much for a manager of your pedigree.
You certainly don’t want to have to go crawling back to that experienced player after your much-hyped youngsters have lost their first couple of games. Better to give the experienced ones a chance to show they can stay relevant to the team.
So Stephen Kenny went with an experienced three in midfield, with Conor Hourihane and Jeff Hendrick, two regulars of the recent campaign, partnering the returning James McCarthy. But some other big names dropped to the bench.
Séamus Coleman had been untouchable under Mick McCarthy, but the captain made way here for Matt Doherty. James McClean was likewise an almost totemic figure for the last two managers, but he too was dropped, as Kenny preferred the more technical Aaron Connolly.
The absence of David McGoldrick and Troy Parrott meant it was a relatively easy decision to use Adam Idah at centre forward. Kenny explained in his pre-match interview that he wanted pace in the attacking areas. Mick McCarthy had always prioritised strength.
It should have been a night when we were all moving on from the second McCarthy era, except that he was commentating on the match for Sky. You can imagine some Sky producer might have thought that getting McCarthy on co-commentary would add a mischievous layer of psychological intrigue, but it was clear from an early stage that it was going be a buzzkill and a waste.
Mick sounded like he was going to guard against the charge that he ought to have recused himself from the game entirely by scrupulously avoiding saying anything interesting whatsoever.
Any insights he offered were strictly unintentional, such as the way he kept insisting that Adam Idah would be “delighted” whenever he accomplished some basic task, as though the young striker’s confidence might shrivel away to nothing with one bad touch.
If this is how he thinks about young players, no wonder James Collins started the 0-0 draw against Georgia one week after Aaron Connolly had scored two great goals against Spurs in the Premier League.
Ireland’s approach was obviously more measured throughout, as evidenced by the final possession count of 63-37 in their favour. There were few of the long balls out of defence that have defined our play for more than a decade.
Moments after kick-off Duffy showcased the new approach; he strode confidently forward into midfield with the ball at his feet, took a heavy touch, chased after the ball and bludgeoned an opponent who had come in to intercept. He is more the stopper than the sweeper in this centre-back partnership. A run forward by John Egan a few minutes later was more successful, but Ireland's attackers seemed surprised to be joined in the attacking third by a centre back and the move came to nothing.
It turned out Duffy’s opening gambit was a portent of things to come. On 56 minutes he ventured forward again towards halfway, and played a short pass to Conor Hourihane in the middle. Unfortunately, Hourihane’s attempted pass towards Hendrick moving down the right wing was slow and telegraphed.
The ball was cut out and transferred down the left, then suddenly into the centre to Todor Nedelev, who looked up and saw Bozhidar Kraev ahead of him, moving into a huge gap between Ireland's centre halves. Nedelev slid the ball through and Kraev beat Darren Randolph with a low first-time finish as Duffy scrambled to recover.
It was Hourihane’s poor pass that created the opportunity for Bulgaria to counterattack, but the goal also looked bad for Duffy.
What had gone wrong? It wasn’t that he had forgotten to get back in position after venturing forward – he’d had plenty of time to get back into the defensive line. But he was caught out by the quick ball infield from the touchline to Nedelev, stranded too far over to the right, and realising too late how much space he had left for Kraev in the centre.
Duffy’s best game for Ireland was three years ago in Cardiff, when he headed everything away as Wales besieged the Irish penalty area. He’s not so comfortable when he has to defend outside the box. Playing for Celtic will at least give him plenty of time to learn about defending on the front foot.
Thankfully for Duffy and for Ireland, he remains unstoppable in the air in both penalty areas. He rescued a draw in injury time with a thumping back-post header from a corner: the oldest-school Ireland goal imaginable. As the team tries to develop new ways to attack, it was comforting to be reminded that there’s at least one old way we can still fall back on.