The Edinburgh-born ex-Hearts and Rangers footballer has been diagnosed with the incurable illness at the age of just 45.
Rumours of Hagen’s MND fight had been circulating online since last week, but the news has now been made official.
Among the well-wishers paying tribute is ex-Ibrox hero Fernando Ricksen, who has also been fighting the deadly condition.
Ricksen said: “It’s always terrible to hear somebody new is diagnosed with MND.
“I want to wish David Hagen, family and friends all the strength they need to fight this demon.
“My advice to him would be to take the MND as it comes, day by day and keep doing the day-to-day things for as long as possible.”
A close friend of Hagen’s said it was a tragedy that the disease had struck so early but added that friends and family would rally around to support him.
They said: “David has confirmed he’s battling MND and he would like to thank everyone who has shown their support at this very difficult time.
“David was a brilliant professional throughout his career and always gave everything on the pitch for every club he played for.
“To be struck down like this at such a young age is a tragedy but he is a fighter and has a close family and many friends to support him.”
The shock news was confirmed in a statement from Falkirk FC, where David Hagen spent five seasons as a player.
Club chairman Margaret Lang said: “The club is aware of rumours that have arisen on social media forums regarding the health and well-being of former Falkirk player David Hagen.
“To prevent further speculation and further attempts by the media to visit him at home – and in consultation with David’s family – the club can confirm he has very recently been diagnosed with motor neuron disease.
“The club is providing to David and his family our fullest support and would ask that their privacy is respected at this difficult time.”
The former midfielder began his career at Rangers before spending a season at Hearts in 1994/95.
During his stint at Tynecastle, Hagen scored 4 goals in 27 appearances.
Hagen was also part of the U16 Scotland team which played in the U16 FIFA World Cup in 1989.
Scotland, who were playing as the host nation, narrowly lost out 5-4 on penalties against Saudia Arabia in the match at Hampden Park.
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