McLean started the round in second place with a six-under 65, one stroke off the lead.
In a seesaw round typical of many, McLean had six bogies, five birdies, and a final hole eagle to card a one-under 70 for the round, and a two round tally of 135, seven-under par.
"It was an up and down day altogether. It was hard to get comfortable, and I had some soft bogies," McLean said.
A run of four birdies in a row on the homeward nine saw Leaney move for a four-under 67 and a share of the honours.
Despite just the one bogey in his round, he said conditions were not ideal.
"The wind was very gusty, certainly tricky...I didn’t make too many fairways but just hung in there."
Chasing a stroke back on 136 were Australians Graig Parry, an amateur Adam Groom, and New Zealand’s Steve Alker.
The 22 year old Sydney born Groom, who only made the tournament after qualifying on Monday, sank a short putt on the 18th for an eagle to cap one of the more better rounds of the day, four-under 67.
The 13-year-old Korean born amateur, Jae An, looked to have lost his chance to make another bit of history when he shot a three over 74, for a two round total of 145, a score likely to see him miss the cut for the final two rounds.
An, who shifted to New Zealand three years ago to further his golf career, was believed to be the youngest ever male to play in a professional open competition.
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Full coverage: NZ Golf Open 2002
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