With 11 minutes left at Celtic Park, the hosts were two more matches from the Champions League group stages. Then it all went horribly, horribly wrong.
Cluj scored to put themselves in front of away goals, then did so again in stop time in front of an aghast Celtic support. It left manager Neil Lennon talking almost disbelievingly about his side now having "make sure we qualify" for the Europa League.
But how much has this defeat – a second in the third qualifying round in two seasons – cost Celtic financially? And how much does it cost Scottish football?
How much does this cost Celtic?
Slavia Prague in the play-off round to reach the Champions League group stage, Celtic would have been 15.25m euros (£ 14.13m). Instead, they should pick up a comparatively paltry 2.92m euros (£ 2.71m).
That's the thick end of £ 12m gone already. But the haemorrhaging does not stop there. As the table below shows, the difference in money received for picking up points in the respective competitions is strong. So, too, is the bounty on offer for reaching the knockout stages.
Then there is Celtic's share of the coefficent ranking pot. That would have been 1.1m euros (£ 1m), based on where the Scottish champions would have ranked among the 32 teams in the groups. In the Europa League, that would pay from 71,430 euros (£ 66,000) to 3.42m euros (£ 3.17m) – but the latter would have been if Celtic were the highest-ranked team in the competition.
What does it do for the coefficient?
It depends. Celtic an automatic four coefficient points for starters, but George Tucudean's goal seven minutes into injury time for Cluj so denied them the half point they would have earned for drawing on the night. That might seem insignificant, but one more draw last season would have been Scotland up from 20th in the rankings to 19th.
A similar scenario unfolded in the early weeks of last season, and Scotland still went on to enjoy a stellar campaign. Both Celtic and Rangers are competing in the Europe League.
Celtic, Rangers, Kilmarnock and Aberdeen have won 12 of their 18 matches so far. That means 13.5 points are already on the page to give a coefficient of 3.375 – which current stands above any other nation in the continent. A strong position on which to build, then, and with three teams still in the Europa League.
How have the fans?
John: "Central midfield most certainly what a problem, why? Because the best central midfielder at the club was playing left-back!" Neil Lennon has not a notion. "
jock: "Callum McGregor is no left back." Huge loss in his natural position. Can not understand why we had £ 10m worth of defenders on the bench watching this calamity unfold. "
Mike: "Neil Lennon, you have to take the blame on this one." Wrong decision to play your best playmaker at full back.
Zayne: There are good teams in The Europa League if we do qualify. "" Defense still needs fixing. "Celtic.
Sean: "Just have to open the book and strengthen it again".
Alan: "Brendan Rodgers sowed the seeds for this chaos with short sighted loans and no forward planning for the defense."