Henry Ayabowei, known as Henry Esin, was found outside Peep in Bangor by police just before 02:00 BST on Saturday.
He was taken to hospital, but died on Sunday morning.
Llanfairpwll football club said Mr Ayabowei was a "true gentleman in every sense".
The 27-year-old father of two from the Llangefni area played football for a number of clubs in the Anglesey region.
The club said: "It is with great regret that we have just heard the tragic news that Henry 'Romeo' Esin has passed away as a result of the injuries received.
"We offer Henry's family and friends our sincerest condolences at this most heartbreaking time.
"Gone but never forgotten, a true gentleman in every sense."
In a tweet the nightclub said: "We wish to offer our sincere condolences to the family of the deceased who was a customer of ours. Our thoughts are with them at this tragic time."
Floral tributes to Mr Ayabowei have been left outside the nightclub and a fundraising appeal for his family has been started.
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