Jason Day can become the No. 1 golfer in the world over the next few days.
The Australian, who has won three of his past four tournaments, will ascend to No. 1 in the rankings from his current No. 3 spot if he wins the Deutschebank Championship in Boston this weekend, so long as the top two players — Rory McIlroy and Jordan Spieth — finish worse than second.
Day, 27, has aspired to a No. 1 ranking since he took up the game seriously in Queensland just more than a decade ago.
"I never thought I'd have the opportunity, mathematically, to get to No. 1," Day said after last Sunday's win in the Barclays. "It's been a goal of mine. Right now, I just can't focus on that. … The only way I can control it is through playing good golf."
Day is to play alongside Spieth and Bubba Watson, bringing together the top three players on the Fedex Cup points table, when the second of the PGA Tour's playoff tournaments begins at TPC Boston late Friday, Australian time. His first-round tee-off time is 11.30pm AEST Friday.
Spieth, the 22-year-old Texan, assumed the world No. 1 rank at the PGA Championship recently but lost it last week to McIlroy.
Only 18 players have held the world No. 1 mantle since the rankings were formalised in 1986.
Greg Norman and Adam Scott are the only Australians to climb to the top of that mountain, the Shark for a total of 331 weeks and Scott for 11 weeks beginning last year.
Five Australians — Day, Marc Leishman, Matt Jones, John Senden and Steven Bowditch — are playing in Boston this week.
Senden, ranked 81st, is the one under most pressure to perform to keep his position for the third playoff event, the BMW Championship. He needs to push himself into the top 70 on the points list to continue and have a hope of playing in the season-ending Tour Championship, which is for the top 30 only.