Sixteen year-old golfer Lydia Ko has today made a 'monumental decision' to become a professional.

New Zealand's top ranked female player made her announcement on Twitter today, accompanied by a video of her playing a round of golf with All Black Israel Dagg who she claimed helped her make the call.

Ko tweeted: Made a monumental decision today with a little help from my @AllBlacks friend @Izzy_Dagg #LOVEGolf.

After forging one of the most successful amateur careers in the history of the game, Ko has long dealt with speculation about when she will assume professional status.


She has foregone winnings of more than $1 million in her amateur career which has included back-to-back wins at the Canadian Open, the first of which made her the youngest winner of an LPGA event.

"This is a very momentous day for Lydia and we are so thrilled that she has chosen such a unique and entertaining way to share her news with her fans today," said New Zealand Golf Chief Executive Dean Murphy.

"Being the special person that Lydia is, she was reluctant to hold a traditional press conference. She didn't want to make a big fuss about news that had already been reported in the media in recent weeks.

"She has also been very busy studying for exams and wanted to make this announcement in a different way."

Murphy said that Lydia's amateur career was exceptional and she has been an outstanding ambassador for New Zealand Golf.

"She has been phenomenal," he said.

"Her amateur record ranks right up there among the greats of the game. She has won four professional titles, claimed the US and Australian Amateur titles, climbed to World No.4 on the World Rankings and has been the World No.1 amateur for more than two years without ever losing that title. That is a record that is unlikely to be matched by a 16-year-old ever again. "

Ko will play for the first time as a professional at the LPGA Tour's season-ending event in Florida.