Dustin Johnson at top of golf's world rankings

Johnson became the 20th player to achieve the top spot in golf since the rankings were introduced in 1986, but confessed to being slightly confused as to how they are calculated.

"I don't really understand it but I can read the one, two, three -- so I guess that's all that matters," the 32-year-old said.

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To us, he's the World No. 1.

But to Tatum, he's just "Dad."

8:12 PM - 19 Feb 2017

 
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Golf's world rankings are worked out over a two-year "rolling" period, according to the official website, with points awarded in tournaments maintained for a 13-week period to ensure an emphasis is given to recent performances.

Tiger Woods holds the record for most time ranked No. 1 with 683 weeks, while two-time British Open champion Greg Norman is a distant second with 331 weeks at the top.

Asked by a reporters what is harder to achieve, winning a US Open title or becoming world No. 1, Johnson sided with the rankings.

"To be No. 1 in the world you've got to play very well for a long period of time. Winning a major is unbelievably difficult too but you only have to play well for four days," he said.

"So probably No. 1 in the world because you're really not going to get there without winning a major -- I mean, I guess you can but it's hard.