Fine margins. It is a phrase used often, but with good reason.
That’s all that really separated the Scottish and Dutch champions, with the latter carrying a clinical edge to capitalise on Celtic’s brief moments vulnerability.
Centre-back Hayes and goalkeeper Daugherty rarely put a foot wrong at the back but while a miscommunication like the one for the opening goal might not be punished on a Sunday in the Scottish Women’s Premier League, it’s a given at this elite level it will be.
Meanwhile, at the other end, Celtic only managed to hit the target with three of their 10 attempts, and those three ought to have been buried.
It’s a tough lesson to take especially ahead of a trip to face Real Madrid next week amid a hectic schedule.
Sadiku will hope Scotland striker Amy Gallacher, who was absent from the squad entirely, will be back in the mix and winger Lucy Ashworth-Clifford, who was deemed not fit enough to come on as a second-half substitute.
Their absence was felt, although summer signings Shannon McGregor, Morgan Cross and Emma Lawton, all of whom were recruited from smaller Scottish clubs, showed they are ready to test themselves at a higher level.
A rare defeat will sting Sadiku and Celtic, as will the fact they missed an opportunity to take points in their easiest Group B fixture on paper, with Madrid and Chelsea still to come.
But there are some positives to take before heading to Spain next week.