The Englishman shot a closing five under par 67 in regulation, including a birdie at the last, to reach 20 under.
54-hole leader Schwab, the young Austrian, could only manage a two under 69 on Sunday but his T2nd finish is his second-best result of his career after the previous week’s WGC-HSBC Champions where he was T4th.
2018 Ryder Cupper Tyrrell Hatton is now up to 30th in the world, therefore guaranteeing a Masters return, and 6th in the Race to Dubai.
“I actually can’t believe that I’ve won,” Hatton said.
“It’s been quite a difficult year in terms of things happening off course and the last month I feel like I really found my game again.
“I said to a few people on my team that if I was lucky enough to win again then I would definitely savour the moment. I think it’s quite easy to take it for granted and sport’s great when it’s going well but when it’s not going well, it kind of hits home, so I’m absolutely thrilled.
“I can’t wait to get that Masters invite through the post again. It’s a special feeling and just a bonus that comes with doing well.”
Schwab, who is up to a career-high 80th in the world, said, “It was a close call. I had some good looks and good chances coming down the stretch in regular play and didn’t take advantage of them. In the playoff, it is what it is.”
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