Celtic's quest for a rare Champions League away victory goes on after having two men sent off in a second-half implosion to hand top seeds Feyenoord an opening group win.
It was a night that began with such promise, as Brendan Rodgers' side started brightly in search of a first away win in the competition since beating Anderlecht in 2017.
But it ended with another painful European defeat that leaves them bottom of the group after Lazio and Atletico Madrid drew 1-1 in Rome.
Things began to go wrong after a mature and composed opening half, when a long-range Calvin Stengs free-kick pierced the defensive wall and skimmed beyond Joe Hart.
The goalkeeper might have done better. The defensive wall might have too. Celtic never quite recovered.
The goal lifted the Dutch champions, who had struggled until then, and they capitalised in the second half as Celtic's night completely unravelled.
Gustaf Lagerbielke conceded a penalty for a tug in the box on Igor Paixao and was shown a second yellow card, before Hart offered some hope with a great save from Paixao's spot-kick.
The task become too great, though, when substitute Odin Thiago Holm crashed wildly into a tackle and earned a straight red.
Alireza Jahanbakhsh then made sure of Feyenoord's win after being gifted time and space to finish emphatically.
It was the least the Dutch deserved, with further efforts disallowed either side of that goal as Celtic hung on. Ultimately, they got away with not losing by a bigger margin.
Lazio come to Glasgow next. An already daunting challenge suddenly looks even tougher.
BDST: 0957 HRS, SEP 20, 2023