A tough and talented New Zealand racehorse and "an uneducated boofhead" with a lot of faith and a rare set of riding skills have won a Cox Plate that proved a triumph for experience over youth.

Ocean Park and Glen Boss made a perfect pair, claiming Australia's most prestigious race at Moonee Valley on Saturday thanks to a simple plan and a final, irresistible surge to the line.

"He just wants to win, he's a winner. Simple as that," Boss said.

"Every time he goes to the races he does a little bit better.

"His will to win is enormous ... he just loves his job and I've got to love him for it."

The victory also made Boss happier than ever with his work, even surpassing Makybe Diva's classic Cox Plate of 2005 and rivalling her three Melbourne Cups.

"This feels like one of my greatest achievements because I picked this horse out in the autumn," he said.

"Everyone kept questioning him. I just kept telling them that he is a winner."

Ocean Park ($6) ran down the three-year-old All Too Hard ($9), grabbing the lead 30m out to score by a neck.

Pierro, the one-time favourite and another three-year-old, ran an honest race to finish third, a further 3-3/4 lengths away.

The other three-year-old, Proisir, finished eighth after leading for much of the race while Ethiopia ran above himself to hold fourth ahead of Shoot Out.

Ocean Park's win also represented a triumph for his trainer Gary Hennessy, a New Zealander of few words, four sons and great horse sense.

"We came here with a plan, we stuck to it and it worked," Hennessy said.

"People weren't sure about him, but I was.

"He goes out and does what he has to do."

Hennessy said he and Boss had devised a plan that involved horse and rider playing a waiting game.

"Glen wanted to be the last one to come off the bridle," he said.

"It didn't work too bad."

Boss said Ocean Park's only mistake was to miss the start by half a length.

But the error proved a blessing, allowing Boss to settle his horse before reaching the winning post the first time.

Ocean Park raced with only three behind him for much of the race with Boss waiting for Craig Williams ahead of him on the favourite Green Moon ($5) to take him into the contest.

"I was on Craig's back but I could see him start to push and he was going nowhere," he said.

"I couldn't believe how fast I went past him."

The pair made steady ground in the run to the home turn but Boss's confidence only rose to a winning level as they straightened.

"Around the turn it was as though he caught sight of the bunny," Boss said.

"He saw All Too Hard up ahead and he surged.

"In the last 100 metres there was no way he wasn't going to catch him."

As he reached the line Boss stood in the irons and acknowledged the win with a trademark shake of the head.

"I can't believe I'm here sometimes," he said later.

"An uneducated boofhead who didn't get past grade ten."

And now a winner of three Cox Plates to match his three Melbourne Cups.