Doral, Florida: Rory McIlroy only grabbed top spot in the world golf rankings on Sunday, but this week faces a direct challenge from the two men who could limit his reign to just seven days.
The Northern Irishman is grouped with world No 2 Luke Donald and No 3 Lee Westwood in the first two rounds of the WGC-Cadillac Championship at the Blue Monster course.
Donald was world number one for 40 weeks until McIlroy overtook him with victory at the Honda Classic on Sunday while Westwood held the top spot prior to Donald's ascent.
Both could return to the top spot with a win at Doral.
While players typically play down the importance of the rankings, insisting their focus is purely on winning tournaments, their grouping is bound to be closely followed.
"I think it adds a little bit of interest. I'm not sure that the players are quite as concerned with it as maybe you guys [the media] or the fans, at least," said Donald.
"But anything that adds to a tournament where the broadcasters can talk about it and add to an event, I think it's probably a good thing.
"There obviously is some jockeying for position. There isn't one stand-out player right now that certainly is what the world rankings would say."