"It's a huge thrill and I'm absolutely stoked," he said. "It's a funny thing, but when he was first being schooled and taught to jump by Matthew, he came in one day and said to me he felt like a real Northern type of horse that would just stay all day.
"I told him he was mad, as he hadn't even had a start at that stage, but it just shows you that sometimes these things are meant to be. He has always been a little slow for the flat but just loves his jumping, with the bigger the fences, the better.
"He had a couple of races at Ellerslie last season and really finished off well, so I thought with a year on him and getting over the Northern distance, then he could be a chance, but you're never confident in a race like this."
O'Leary will spend summer planning a schedule for Te Kahu which could include an Australian sojourn if he comes up well for a new campaign.
"We'll get him home and let the dust settle before we do anything with him, but he's a young horse that still has it all ahead of him."
One race earlier, The Cossack cemented his reputation as one of the best hurdlers of modern times when he defended his title in the Great Northern Hurdle (4200m).
The Paul Nelson and Corinna McDougal-trained 8-year-old has swept all before him this season, adding his second Great Northern title to victories in the Waikato Hurdle (3200m), Wellington Hurdle (3100m) and Grand National Hurdles (4200m).
There was a dramatic aftermath to the Great Northern, with rider Emily Farr transported to hospital via air ambulance after a fall from Kaharau that saw her knocked unconscious while also suffering a punctured lung and a potential break under her left eye.
Two other jockeys also suffered significant injuries on the day, with Craig Thornton breaking his arm when falling from Lacustre in the Great Northern Steeplechase, while Gary Walsh broke his left thigh after a fall from Jakki Sparrow in a maiden hurdle contest.
- NZ Racing Desk