"As the day went on it progressed up my left arm. My whole left side went completely dead, and I thought I had had a stroke to be honest."
Tony went to see a neurologist, who suspected he had contracted a viral infection and prescribed steroids.
However, within a couple of months Tony's symptoms started to deteriorate.
"Everything went completely haywire. I lost all my energy, my co-ordination went out the window, my memory disintegrated totally," he said.
Tony tried to continue to play professional golf, but his symptoms were so problematic that he had to walk off the course several times.
He was particularly hard hit during a practice round prior to trying to qualify for the British Open in 2004: "It was like somebody had pulled the plug on me - I could hardly walk."
An MRI brain scan confirmed that he had MS.
My memory had come back, my co-ordination was improving, and within six months I realised I had been a very lucky boy
Fortunately, he was recommended for the alemtuzumab trial, and squeezed in just before it was closed to new patients. At that time the drug was known as campath.
He received two treatments, a year apart. The first, five-day session effectively shut down his immune system, allowing it to re-boot, without the fault that causes it to attack the nerves, and trigger MS.
The second, three-day session, 12 months later acted as a back-up to ensure the treatment was working.
"For the first couple of months you feel very tired - it has been likened to the feeling of chemotherapy, they shut down the immune system, and you feel fatigue," said Tony.
"But after the first treatment, probably within three months, I realised there was really a vast improvement.
"My memory had come back, my co-ordination was improving, and within six months I realised I had been a very lucky boy."
However, the road back to professional golf turned out to be long and hard.
"I thought it was going to be like riding a bicycle, get back on and carry on again," said Tony.
"But I would say it took two years for me to find a way to work around it, by thinking different thoughts, and feeling different feels in the golf swing - but I was pretty determined to get back to competing again."
"There is a way round it if you are determined - with the help of campath, without that I just would not have been able to do it."
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.