Aucklander Sacha Jones has become the New Zealand tennis No 1 after three consecutive WTA tournament victories over former top-10 player Alicha Molik in Australia in recent weeks.
As her WTA world ranking improved from 242 to 208, the 18-year-old passed Marina Erakovic, whose world ranking has slipped to 240after an injury-marked year.
Jones said the No 1 ranking was an honour, but there were "up to 208 in the world, so there's just another 207 to go".
"I've been working really hard in training. Since December I've been working on specific things in my game and it's just in the last month that everything I've been working on in practice has fallen into place in my matches and I've started to execute much better.
"It's just a whole plethora of things that mould into your game."
Jones leaves on Thursday for a series of tournaments in the US and returns home before Christmas to prepare for competitions in the southern summer.
Despite her WTA ranking of 240, Erakovich has a protected WTA ranking of 83 which she can use to get entry into eight tour events. She is through to the final round of qualifying at an ITF US$100,000 ($133,000) tournament at Ortisei, Italy. The 21-year-old has won her opening two matches, to reach the final round of qualifying.
Erakovic won her first round with a 7-6, 6-7, 6-2 victory over Italian Alice Moroni, before notching up a 6-4 7-6 win over Czech Kristyna Pliskova. She played Romanian Elora Dabija overnight for a place in the main draw.
She reached a career-high 49th in July last year and was 83rd when forced off the circuit in March.
Erakovic's "special ranking" is based on a player's ranking following their last tournament played.
She is playing for the first time in seven months after being sidelined with hip and ankle problems.
Meanwhile, New Zealand men's No 1 Dan King-Turner won his third ITF singles title of the year over the weekend with a victory at the Nonthaburi Futures in Thailand.
King-Turner recently had his ranking improve to well inside the top 300.
