Brendan Rodgers was accused of perhaps being too gung-ho against Borussia Dortmund.
Celtic crumbled that evening, on Champions League matchday two, and were punished with a whopping 7-1 hammering in Germany.
The manager refused to compromise with his tactics and demanded his players go out against the Bundesliga giants and try to give as good as they got while remaining defensively stout.
Things didn’t quite work out that way, though – a fact that Rodgers acknowledged and accepted blame for – but he appeared to learn a valuable lesson.
Last night as the Hoops put in what was a terrific defensive display, Rodgers was delighted to keep a clean sheet against one of Italian football’s highest goal scorers.
The Black and Blues did have their chances but the likes of Kasper Schmeichel, Auston Trusty and Liam Scales in particular were imperious for the visitors.
Celtic up front, meanwhile, were seriously starved of chances but it was just one of those evenings.
Atalanta were held to a 0-0 draw by Celtic in the Champions League
And asked to reflect on the changes between last night and the Dortmund humbling, Rodgers took into consideration the previous calls from fans and pundits to be a tad more defensive in their mindset.
The Northern Irishman even used it as a point with which to prove he had acted.
“It gives them (the squad) the confidence that they can defend against the top teams,” he said.
“I said that. I’m not sure whether that was pragmatic enough for people tonight, I don’t know.
“We go out in every game to be structured and defend well, you want to get pushed back, but I think the confidence it gives you when you can defend against the best teams…
Rodgers was accused of failing to keep the backdoor shut against Borussia Dortmund
“At that level, that concentration, it will give them a huge boost.”
Goalkeeper Schmeichel was to thank in the first half when he made two huge stops to keep out Mario Pašalić who also cracked the crossbar with a header.
Arne Engels and Kyogo only really tested stopper Marco Carnesecchi with half-chances.
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