The injured Rory McIlroy is unable to defend the Claret Jug at this year's Open yet he may be keeping a nervous eye on proceedings with his No1 world ranking under threat from rising star Jordan Spieth.
The Norther Irishman has held golf's No1 spot since winning the Bridgestone Invitational last August, when Spieth was not even in the top 10.
Yet the Texan has enjoyed a game-changing 2015 in which he has become only the fifth player to win the first two Majors in a calendar year. Since the turn of the year - when he was ranked the 9th best player in the world - the current No2 has rocketed up the standings, making a beeline for McIlroy's lofty position.
And this week he can seize the top spot from the absent reigning champion by adding a third consecutive Major title, becoming just the second player in history to do so in the process (Ben Hogan was the last in 1953).
By winning in his debut at St Andrews, Spieth would win the 100 ranking points up for grabs at all Majors and boost his points average - the determining factor for the official world golf ranking - over McIlroy's 12.52.
Ranking points are accumulated over a two-year rolling period, with points incrementally diminished after a 13-week period, hence why Spieth's recent wins have sent him on such a steep upwards trajectory.
To win the 144th Open and become the fifth American golfer to take the No1 sport, Spieth will have to successfully negotiate a course he has never played before known for being one of the most treacherous there is.