Published Monday, 05 March 2012
Rory McIlroy poses with the trophy after winning the Honda Classic (© Getty)
At just 22 years of age, Holywood player McIlroy is the second youngest man ever to hold the top spot since rankings began.
He produced a masterful display in Florida, dropping only one shot in a final round of 69, en route to his third PGA Tour victory - holding off a late charge from a resurgent Tiger Woods.
Woods later took to Twitter to congratulate the Ulsterman on his latest achievement.
He wrote: "Congrats to @mcilroyrory on getting to no 1".
Meanwhile Scottish golfer Colin Montgomerie said McIlroy could be poised to dominate the top of leaderboard for some time.
"Two years ago Tiger probably would have snatched it after coming up in the rear-view mirror," said Europe's 2010 Ryder Cup captain.
"But all credit to Rory for being stronger and more mature.
"You get Woods scoring 62 in the last round and you still win - that's a very good effort, isn't it?
"The best of luck to him. He could be number one for a while."
Last week, US Open champion McIlroy missed a chance to dethrone Donald at the top of the rankings when he lost the final of the Accenture Match Play in Tucson to American Hunter Mahan.
But he held his nerve over the weekend and gave a display worthy of his newfound title.
Donald also applauded Rory on Twitter, adding: "Enjoy the view!"
McIlroy previously won at Quail Hollow in 2010 and, in 2011, he became the youngest winner of the US Open since 1923.
He is the fourth European in a row to head the rankings following Westwood, Martin Kaymer and Donald.
Meanwhile fellow Northern Irish golfer and former US Open champion, Graeme McDowell, branded his friend "the best player I've ever seen".
"He deserves it," McDowell said. "I think he's the best player on the planet right now.
"He's the best player I've ever seen tee-to-green, period. I didn't have a chance to play with Tiger early-to-mid-2000s when Tiger was the man, but Rory McIlroy is the best player I've ever seen."
© UTV News