Long established as world number one, Tiger Woods runs the risk of being deposed at the top of the rankings in the first quarter of next year.
The American has been out of action since having reconstructive knee surgery after winning the U.S. Open in June and, as a bystander, has watched his stranglehold at the top steadily loosen week by week.
After his astonishing playoff victory at Torrey Pines six months ago, Woods enjoyed a substantial lead of 11.328 ranking points over second-placed American Phil Mickelson.
Spaniard Sergio Garcia has since climbed into second spot in the global pecking order and trails Woods by just 3.865 points going into the New Year.
The game's dominant player is unlikely to return to competitive golf until at least late February and his number one status could be usurped by Garcia, world number three Mickelson or fourth-ranked Irishman Padraig Harrington.
For Woods to surrender the grip he has held since June 2005, one of his rivals would have to make a fast start to 2009 while also winning at least one of the big tournaments early on.
World ranking points are weighted according to the status of the event and strength of the field and the WGC-Accenture Match Play Championship in Tucson and the WGC-CA Championship in Miami provide rich reward in the first three months.
Ian Barker of Official World Golf Ranking (OWGR) has examined projections of the rankings on a month-by-month basis leading up to the Apr. 9-12 Masters, where Woods is determined to compete.
"These projections show how, as time passes, Tiger's position at the top becomes more vulnerable," Barker told Reuters.
"If you look at the March 29 projection, you will see I have input seven events and the number of points that Garcia and Harrington would need to pass Tiger's average on that date."
Although Barker is speculating about the playing schedules for Garcia and Harrington, he has assumed the seven events in which each competed during the same period earlier this year.
"Sergio needs 81 OWGR points from those events and Harrington needs 144," Barker said.
"A WGC (event) will carry winning points in the 70s so it is possible for both players (to overtake Woods) but I don't think either could do it without winning a big tournament."
Of course, much will depend on when Woods does return to the game and how effectively he is able to play.
The Masters, the opening major of the year, is his first priority for the 2009 season and ideally he would like to play in a couple of events before that in preparation.
The Accenture Match Play in Tucson in late February is a possibility for his much anticipated comeback, although the March 12-15 CA Championship is more likely.
For the moment, however, the 14-times Major winner can reflect on the record total of 529 weeks he has been golf's world number one during his career.
He first claimed the top spot on June 15, 1997 and has held the position since regaining it from Fiji's Vijay Singh on June 12, 2005.