UPDATE: Central Queensland's Jason Day has become golf's world No. 1 after winning the BMW Championship by six shots.
When a teenaged Jason Day told the golfing world he wanted to become the number one golfer in the world, people smirked at the audacious goal. Nobody is laughing now.
Winning the BMW Championship this morning has catapulted the 27 year-old into the prized position on the world golf rankings list.
Day becomes the third Australian to reach the number one spot, behind Greg Norman and Adam Scott, but he's the youngest of the trio to ascend to the of the list.
The long road from Rockhampton to golfing greatness finished with a birdie on the par-5 last hole this morning to secure a six-shot win over Daniel Berger with Scott Piercey a further shot back in outright third.
The win caps off an extraordinary run for Day who has now won four of his last six tournaments. Prior to that he had two Top-10 finishes in major tournaments in the US Open and The Open Championship.
Day said it was at St Andrews when he left a birdie putt short on the 72nd hole to narrowly miss out on a playoff berth that changed his mentality.
"Ever since The Open Championship, something changed in my head and I felt like it was time to start winning tournaments and ever since then it's been a phenomenal run," Day said.
The winning run has been rewarding as well.
Since teeing-off in the US Open three months ago, Day has won an incredible $US6,774,293.
He is now in the box seat to claim the $US10m bonus next week for finishing on top of the USPGA Tour's FedEx Cup rankings for the year.
For Day though today isn't about the money, it's about realising a boyhood dream.
"The main goal was to get to number one and we (Day's team) understood that you had to win consistently and you had to win to get to that number one spot," he said.
"To be able to have the opportunity to get to number one and win was fantastic."
Having shot a 61 and 63 to open the BMW Championship, the tournament was there for Day's taking.
He admitted that knowing the number one ranking was there for him made the final 36 holes a tough affair.
"I felt a lot of pressure over the last two days, especially today, knowing that I had a six-shot lead. Things could happen. Some guy could shoot a low score or maybe I could shoot one or two-over."
EARLIER: JASON Day failed in his bid for a historic 59 but he is on track to be golf's world No.1 after extending his lead after two rounds at the BMW Championship.
Day holds a five-shot lead at the halfway stage at Conway Farms Golf Club in Illinois, sitting at a stunning 18-under par.
He had to hole a 40-metre pitch shot on the 18th from deep rough to complete his first round on Friday - after thunderstorms ended play early on Thursday - to become just the seventh player in US PGA Tour history to card a sub-60 round.
But Day's improbable eagle attempt with his 60-degree wedge ended up nine feet short and his putt lipped out, leaving him with a 10-under 61.
Day then turned around and backed it up with a sizzling second-round 63, finishing with a 43-foot eagle putt on the last.
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