Hawthorn coach Alastair Clarkson.

Hawthorn coach Alastair Clarkson. Photo: Ken Irwin

What is Guillane-Barre?

Hawthorn is unsure how long it will be without coach Alastair Clarkson, who has shown promising initial signs in his recovery from a rare and serious auto-immune condition.

The Hawks are preparing to be without Clarkson for three weeks or more after he was diagnosed with Guillain-Barre syndrome - a form of nerve inflammation affecting the spinal cord - but will not know when he will be ready to resume work until he has undergone further treatment.

While the club has been given confidence that Clarkson, 46, will make make a full recovery, chief executive Stuart Fox said his recovery time was "open-ended'', with  the disorder affecting some people for months and even years.

Clarkson was admitted to hospital on Monday night after the back pain he had experienced in the previous week became more severe. His condition was quickly diagnosed and treatment started.

Assistant coach Brendon Bolton will step in as senior coach this week and may hold the position for several weeks, with Clarkson expected to remain in hospital for at least the next week.

Fox said Clarkson's health was the club's sole consideration, and he had been told the quick diagnosis was good news, as was his positive response to treatment on Monday night.

The symptoms of GBS can range from mild to life-threatening, depending on which nerves are affected, and include muscle weakness, numbness, muscular pain, breathing problems and dizziness. The condition causes a person's immune defence system to attack the body's nerves, and is often preceded by a viral or bacterial infection. Most people recover, but it can take considerable time.

"It is a serious condition, but he's been diagnosed very early and the medical team we have in place around Alastair are confident he'll make a full recovery. He had treatment as soon as he was diagnosed and he's responded well to that,'' Fox said.

"It's very open-ended, and we're only concerned about his health. We think it will take a few weeks for him to recover, but it may be more and we can only go by medical advice on that.

"He's had a bit of back pain in the last week and thought it was an old football injury, as most people probably do with little niggles, but the pain became quite acuteand so he was admitted and diagnosed late in the evening.

"There can be a serious recovery time involved, but he's in good spirits, he's got the best possible people around him and they've been very positive.

"The doctors have said, if you can get it early there's usually positive signs for recovery. We'll just deal with it each week. We've got a plan in place whether he's here in one week's time or 10 week's time. Continuity in the workplace won't change."

Shocked and concerned after learning of his coach's predicament, Hawthorn captain Luke Hodge expected the players to respond positively to Bolton, who has worked alongside Clarkson for six years and will be supported by fellow senior assistant Brett Ratten and the other coaches.

“He spends a lot of time with Clarko. They’re exactly the same, their mindsets are the same for the game,'' Hodge said.

“It’s different not having Clarko there, but the messages and how we’re going to play will be exactly the same.”

Hawthorn recruiting manager Graham Wright spent four weeks in hospital with the illness as a 25-year-old Collingwood player in 1993, and said later he had struggled to walk and talk when at his worst, taking around three months to recover. He returned to play five more seasons with the Magpies.

Former Richmond chief executive Steven Wright was also hospitalised with the condition late in 2006. Wright resigned from the club three years later for health reasons.

Hawthorn was last forced to replace an unwell coach in 2001, when Peter Schwab was diagnosed with a benign arrhythmia of the heart before the club's round-17 match. He was taken to hospital on the morning of the game, to have the problem corrected with mild electric shock treatment. Assistant coach Chris Connolly stepped in for Schwab, with the Hawks beating Carlton when Ben Dixon kicked a goal after the siren.

Famously, Alan Joyce coached the Hawks to the 1988 premiership while covering for Allan Jeans as he recovered from brain surgery. Jeans returned to coach in 1989 and steered the team to another flag.