(CNN) -- American golfer Bill Haas said he was "very lucky" after securing the biggest win of his career on Sunday. The 29-year-old beat U.S Ryder Cup star Hunter Mahan on the third playoff hole at the Tour Championship in Atlanta to clinch the PGA's season-ending FedEx Cup and $11.44 million in prize money. Haas needed a dramatic save after hitting a water hazard before going on to sink a four-foot putt on the par-three 18th hole at East Lake to finally see off his compatriot, after the duo had finished tied on eight under par through 72 holes. The dramatic triumph saw Haas -- whose father Jay played in the Ryder Cup on three occasions and won nine times on the PGA Tour -- leap from 25th in the FedEx Cup standings to claim the $10 million jackpot.
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Bill Haas clinches the Tour Championship and FedEx Cup titles after playoff
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American claims $11.44 million in prize money at end-of-season event in Atlanta
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He defeats U.S. Ryder Cup star Hunter Mahan to seal his big-money triumph
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World No. 1 Luke Donald ties for third, ending his hopes of historic double
FedEx Cup
FedEx Cup
FedEx Cup
"I guess this is what the @placeholder is all about," said Donald, who would have claimed victory in the series if he had finished alone in third.
Luke Donald
"I guess this is what the FedExCup is all about," said @placeholder, who would have claimed victory in the series if he had finished alone in third.