Jordan Spieth
Sep 27, 2015; Atlanta, GA, USA; Jordan Spieth with the tournament trophy and FedEx Cup trophy after winning the final round of the Tour Championship by Coca-Cola at East Lake Golf Club. Reuters/Jason Getz-USA TODAY Sport

Jason Day failed to continue his reign as world No. 1 after losing out at the Tour Championship in Atlanta on Monday, with Jordan Spieth winning the four-event tournament to bag home the $10 million (AU$14.2 million) prize money after topping the season’s FedEx Cup points competition.

Day failed to replicate his remarkable run in two of the FedEx Cup playoffs event after firing a final-round 68 to finish in a tie for 10th place at the Tour Championship, eight shots behind Spieth, who closed out the tournament at 9-under-par overall to get a 69 for the round. Day, who has now slipped to No. 2 in the world rankings, needed to end the Tour Championship at a three way tie for fifth or better to retain this throne as world No. 1, but the 27-year-old Aussie failed to carry his brilliant performance at the BMW Championship into the final round of the playoffs.

"It's been a good year,” Day told 9news. “To be able to win a Major Championship, the PGA Championship, and then also to get to No. 1 has been a life-long dream of mine.”

Day also dropped his bonus money from $3 million (AU$4.2 million) to $2 million (AU$2.8 million) after Henrik Stenson made a 57-foot birdie on the last round, putting the Australian golfer to third in the season-long points standings of the FedEx Cup. But despite a disappointing finish at East Lake Golf Club, Day is still positive about all his achievements this season, making him “more hungry” to reclaim the top of the world golf rankings.

Meanwhile, Spieth impressively ended a brilliant season, scoring a four-shot victory at the Tour Championship. Spieth missed the cut in the first two event of the FedEx Cup playoffs, but still managed to snatch his fifth win of the season, virtually clinching him the Player of the Year honours.

"This is incredible,” Spieth said, reports the ABC. “This is an event that we approach like a major championship because we know this is possible at the end of it.”

New Zealand’s Danny Lee, England’s Justin Rose, and Stenson shared second place at five under. Steven Bowditch finished at even par for the championship and tied for 12th.

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