The world's second, third and fourth-best golfers all have a chance of usurping Luke Donald at the top of the world rankings with a favourable result at this week's Open Championship.
If Donald misses the halfway cut at Royal Lytham & St Annes then number two Rory McIlroy will need a top-two finish, while third-placed Lee Westwood would have to win with Donald outside the top three.
Tiger Woods could also become number one for the first time in 21 months if he wins his fourth Open title and Donald doesn't finish second or third on his own.
The tee-off times for the opening two rounds of the major were released earlier today. See the pick of the trios here.