Celtic are set for their first ever journey to Bosnia in European competition in the Champions League qualifying first round on Tuesday.
FK Sarajevo might be a relative unknown quantity to most Hoops.
But that doesn't mean they won't pose a threat.
Especially not if the passion of the supporters in the former war-torn region is anything to go by.
A short documentary 'Derby Days' featuring a Željezničar vs Sarajevo clash from 2014 goes deep inside the intensity and fierce rivalry with which the two local sides live side-by-side.
The organised Ultras group that supports Sarajevo, Horde zla, will provide the Hoops with a red hot welcome inside the 34,500 capacity Asim Ferhatovic Hase Stadium.
And as the narrator explains, football is everything to the diehards that support both sides in the Balkan country.
Having been starved of professional football during the troubles in 1991-94, the locals still turned to the "magic ball" to stay sane and healthy and escape the horror.
The result was that football is the number one passion in the city and while rivalry is red hot between Sarajevo and Željezničar there remains a respect between the two sets of fans.
Celtic can expect flares, colour and ferocious intensity from the home sections when they run out into the Bosnian heat on Tuesday evening.
Neil Lennon's side should have too much class on the park. But with the backing of the 'Horde zla', their hosts might just have that extra fire in the belly to make life pretty awkward.
