The Aucklander equalled his fourth place finish at New Orleans from just two weeks ago.
His only previous top-10 finish was at the Zurich Open of New Orleans team event.
The Japanese-born Cantabrian won his spot with early success on the PGA Tour of Australasia Order of Merit.
The golfing great will back at Pinehurst next month.
Ryan Fox and Garrick Higgo finished tied for fourth in New Orleans.
The pair sit in a share of 27th with a round to play at New Orleans.
The duo have fallen to a share of 26th.
The two sit in a share of eighth at the team event in New Orleans.
Ko is still needs one more tour title to automatically qualify for the LPGA Hall of Fame.
Lydia Ko is inside the top 10 heading into the final day in Texas.
Lydia Ko has carded another solid round at the first LPGA Major of the year.
Lydia Ko shares fourth after her opening round at the Woodlands.
The Northern Irishman has been one of the most vocal critics of the breakaway tour.
The world number one finished four shots ahead of second.
Ryan Fox found the water on the 16th to cap a tough day on the course.
The Kiwi has put together another mixed performance.
It’s been a day to forget for the five-time champion.
The Kiwi has finished one-under after two rounds.
The five-time champion will remain in the competition over the weekend.
The world No.54 sits four shots behind leader Bryson DeChambeau at Augusta National.