The 25 year old chipped in for eagle at the 11th to get back in the hunt and then had three birdies in the last four holes – including the last two – for a six under par 66, stealing the title from South African Jaco Van Zyl, who could only par the last for a 67.
Thailand’s Kiradech Aphibarnrat took third place after signing off with 67, while Korean Byeong Hun An was fourth thanks to a 66.
The expected challenge of World Number Three Rory McIlroy never materialised, a one under par 71 leaving him tied sixth – although he extended his lead at the top of the Race to Dubai after second-placed Danny Willett finished tied 11th.
It was an emotional Dubuisson who spoke after his win.
“It means a lot because I haven’t had a great season so far and to win here, to get back in the top ten of the Race to Dubai, is really great. For personal reasons I haven’t played a lot this season, and when I have it’s not been great. I was still in the top 50 in the Race to Dubai, but I was expecting more compared to the 2014 and 2013 seasons. Winning this week, I couldn't dream of anything better.
“My putting was really bad this year and my short game, as well. But it's because I didn't really have time to practise a lot. When you start to putt really badly, then you lose your confidence. I decided to change my putter two months ago, and now, it worked pretty well this week. It was definitely my week on the greens.
“On the 18th I was sure Jaco would make birdie, so I just tried to make a big drive and take my chance. The chip on 11 – at that time of the tournament every shot is very, very important. I was really counting on the three par fives on the back nine. To make eagle was just amazing and it arrived at the best time.”
The leading Australian of the two who played the event was Richard Green who finished 37th with Marcus Fraser 47th.
The European Tour now moves to Asia for this week's WGC HSBC Champions event in China.
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