Fox arrived in New Zealand on Tuesday after playing in the WGC-Mexico Championship where he finished in a share of 29th place.
Starting on the back nine of the Arrowtown course, Fox shot a five under 31, including back-to-back birdies on 16 and 17.
Joining him on five under was Korea’s Joohyun Kim, who eagled the par 5 10th at Millbrook.
Defending champion Zach Murray and 2014 winner Dimitri Papadatos had a share of third place a shot behind the leaders.
