'The speed of tennis, the energy spent when playing - it was getting harder for me, which is why I turned to golf,' Fung recalls. 'But then I quickly realised that golf is actually a much more difficult game to play well, but by then it was too late. I was hooked.

'I desperately wanted to become a professional. I spent a lot of money playing golf when I was in Canada. Looking back it was risky, which is why I had to make it. Luckily, my family was supportive.'

While the in-form teenage amateur pair of Steven Lam Tsz-fung and Jason Hak Shun-yat will undoubtedly be the focus of attention at the UBS Hong Kong Open, which begins on November 12, spare a thought for Fung who - unless the organisers announce British Open runner-up Tom Watson as part of the line-up at Fanling - will be the oldest player in the field.

Two weeks ago, Fung booked his place alongside golf's elite by overcoming nearly 40 of the best local professionals and amateurs to win the qualifying tournament at Kau Sai Chau.

Firing solid rounds of 72 and 73 over the demanding Gary Player-designed North Course, Fung edged out his nearest competitor, Lee Man-lok, by two shots. With four spots up for grabs, Lee also qualified, along with former Hong Kong international Derek Fung and Chris Tang Shing-shi. But it was the performance of the senior that caught everyone's attention - and not just because of his age.

'Even I was surprised,' says Fung, an instructor at the Garden Farm Golf Centre in Sai Kung when he is not working on his game. 'Although I'd been preparing for the tournament for six months, I've been trying to make it through qualifying since it was introduced [in 2006] but have never come close. I thought this might be my last chance, so I'm very happy and very proud I've managed it.'

He returned from Canada in 2000 and spent countless hours on the range and taking in the advice of his coach, former Hong Kong Golf Club and Clearwater Bay Golf Club instructor Lee Parker, who created the Hong Kong Professional Golf Association's first professional training programme.

'I played a lot at Kau Sai Chau and practised every chance I had,' Fung says. 'When I was ready I took the HKPGA training course. I passed it in 2005 and my dream had come true.'

Four years on and he is playing the best golf of his life. Just prior to his qualifying heroics, he made the cut in both the Malaysian and Taiwan senior opens.

The secret of his success? Fitness.

'Physical training is very important for me,' Fung says, echoing the mantra of the modern breed of playing professional. 'I'm in the gym working on improving my strength regularly and I go jogging four times a week. Being fitter has enabled me to concentrate better on the course. I've seen a difference this year especially.'

The newcomer, who counts Nick Faldo, Fred Couples and Ernie Els as his favourite players, isn't concerned about who he is drawn with during the first two rounds at Hong Kong Golf Club at Fanling - 'I'm just delighted to be there,' he says - nor is he worried about being the oldest player to tee it up. His focus during the days leading up to the event is on getting plenty of rest.

'I really don't have any expectations,' he says.

'But if I can sleep well the night before then I will play well. I don't tend to get nervous, but if I can't get a good night's rest then it really affects my game.

'I think Fanling is a great golf course and naturally I'll be trying to make the cut - and if I do so that would be great. After qualifying for the tournament my students took me out for a very nice lunch, which was kind of them, and they asked me what I thought about playing in the same tournament as all the famous young pros. I told them I really don't mind being the old guy there. You know, I really don't mind having that title.'

Senior citizen

Unless there is a late entry, William Fung will be the oldest player in the HK Open

After a lifetime playing tennis, William Fung's years in golf add up to just: 13