Llantwit Major began their latest Fenix Trophy journey with a 7-2 defeat to Berchem Sport in the first round of their first leg clash.
The Cymru South club were the visitors at the Belgian amateur league side before a capacity crowd of over 1500 on the outskirts of Antwerp on Wednesday night.
The two sides will meet again for the return leg in Bridgend next month.
Berchem, who have won just one league game so far this season, raced into the lead as Kelvin Owusu broke the deadlock in the first minute.
Before the first half hour was up, Owusu had claimed a hattrick with Ambrose Frimpong scoring the hosts' third goal from a corner.
But Llantwit, who are unbeaten in their last seven league games, pulled one back as sub Josh Morgan headed home past the keeper on 33 minutes.
Yet barely two minutes later, Berchem restored their four-goal lead via Brend Lambrechts.
Six minutes after the break, Llantwit youth product Madison Armstrong - who made his first team debut in July - scored his first senior goal from a corner.
But Berchem still found net twice in the second half - with a superb Len Vennekens strike and a Nikola Pejcic penalty to put the Belgians in cruise control.
Llantwit admitted afterwards they had been "taught a lesson" by Berchem, but nothing could take away from the occasion and another unique excursion into European football.
A club spokesperson tweeted: "We cannot thank our fans who travelled tonight enough. Non stop singing throughout the game and huge appreciation of the boys hard work."
The second leg takes place at the STM Glass Stadium on Wednesday 13th November. Meanwhile, Llantwit resume their Cymru South campaign when Newport City visit Windmill Lane this Saturday (2pm ko).

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