Belen Mozo has stormed into a five-stroke lead at the New Zealand Women's Open at Windross Farm Golf Course in Auckland with a superb eight-under second round 64.

Her round included a hole in one at the par-three 13th, the 29-year-old Spaniard catapulting into the lead after sitting in a share of third overnight.

In addition to her eagle, Mozo - ranked 206th in the world - fired eight birdies to hold a commanding lead over unheralded American Emily Tubert, Canada's Brooke Henderson and 24-year-old Swedish golfer Madelene Sagstrom.

Mozo's only blemish came when she double-bogeyed the par-three 17th, but she rallied to finish with a birdie on the 18th.

Earlier, Tubert had shot seven birdies in her seven-under 65 to grab the early lead on nine-under for the two rounds.

Tour rookie Tubert, ranked 489th in the world, reached all 18 greens in regulation, taking advantage of relatively mild conditions to soar from her overnight placing of 20th.

Henderson had shared the overnight lead with Englishwoman Jodi Ewart Shadoff on seven-under 65, remaining in touch with a steady two-under 70 in round two.

Ewart Shadoff dropped off the pace with a one-over 73, dropping into a share of 12 place with six others including New Zealander Lydia Ko.

Ko's error-free round left her on a two-round tally of 138, eight shots shy of Mozo, but only three astray of Tubert, Henderson and Sagstrom.

The former world No.1 said her second round was encouraging going into the final two rounds sure to be in front of packed galleries.

"I made a few putts for birdies," Ko said. "I missed a few too but I made a few more than I did yesterday.

"There are lot of positives, a lot of solid things in my game the last couple of days.

"But I know there's a lot of golf to be played, so I've just got to focus on my game and go from there."