|Fernando Ricksen made 182 appearances for Rangers between 2000 and 2006|
Photo: SNS Group
News surrounding the 37-year-old's life-threatening condition only emerged on Wednesday night during a Dutch TV show De Wereld Draait Door.
Clearly struggling with his speech, Ricksen was asked: "You talk slowly at the moment. Why?"
Ricksen, who was promoting his new autobiography on the show, replied: "At the moment, I have a little trouble talking. I've been seen in hospital with ALS (Amytrophic Lateral Sclerosis - the Dutch term for MND)."
The disease is a terminal illness that kills the motor neurones - the nerve cells that send messages to the muscles so the body can move.
As the illness progresses, the patient eventually becomes entirely paralysed - unable to move, talk, swallow or breathe, but still able to see, hear and feel.
There is no cure for the illness and the only licensed treatment is the drug riluzole, which can slow the progression of the disease, but only for up to six months.
An Italian study in 2005 revealed that footballers are at least six times more likely to develop the disease than others.
"Inside me there is a fighting spirit, there always has been. I will fight this - I know it will be difficult but I will battle all the way," added Ricksen, who captained Rangers for much of the 2004/5 season.
"I have Veronica and Isabella - they are my second life and I have to try."
The Dutchman has faced many fights during his career, and has coped with alcohol addiction in the past, but this battle with MND is going to be his toughest.
Fighting back tears, Ricksen said: "The medical people have said my condition could worsen quickly. I do not know anymore."
Many of his fans and friends took to social media to send messages of support to the former Dutch international.
I'm saddened to hear the news about Fernando Ricksen! My thoughts and prayers are with you and your family at this difficult time! God Bless— Stiliyan Petrov (@StanPetrov19) October 30, 2013
Just heard the news about Fernando ricksen. Thoughts are with him and his family— Charlie Adam (@Charlie26Adam) October 30, 2013
:( I just heard the very sad news about fernando ricksen suffering from motor neurone disease !! My thoughts are with him and family !!— Bobby Petta (@bobbypetta) October 30, 2013
Dreadful news on Fernando Ricksen tonight. Our thoughts with him at this terrible time.— Rangers Supporters (@rangersfctrust) October 30, 2013
Previously, Ricksen has admitted to living a relatively hard life, with lots of drinking and partying.
He told the Daily Record in August: "After a match I'd stay up drinking until four or five in the morning and I'd spend the rest of my week quietly. Train, play, drink, train, play, drink.
"If you trained well and looked after yourself, you could last out a long time. I took good care not to take to the field when I was drunk.
"I have attended a clinic and have been to meetings. I know I have a problem, and I say, 'I am an alcoholic.'
"I can’t promise never to drink again. Perhaps I can for one day. I have my ups and downs. I have drawn up a program for myself and I try to stick to it. Hopefully I won't be drinking any more in 10 years."
In his career, Ricksen played for Fortuna Sittard, AZ Alkmaar, Rangers, and Zenit Saint Petersburg, whilst also representing the Netherlands on 12 occasions.