Stung by a narrow defeat a few years ago, such is Payne's passion for the Grand Annual, he has replicated the famous cross-country course on his Plumpton property, north-west of Melbourne.

"It's the exact replica of the course, it's pretty makeshift, it's nothing special," he said.

"We've got like a sand track and there's a jump before it and a jump after it so he's got to jump the jump, go over the sand track and jump another jump.

"That's how special this race is to us. We got beat one year and I think we got the corners wrong so I think the last four years we weren't going to let this happen again.

"You can lose a length or two and that can be the difference."

The win carried significance on several fronts. Zed Em lumped 70 kilograms, the most since The Feline in 1950, who carried 74 kilograms. Zed Em became just the eighth horse in 143 years to win both the Great Eastern Steeplechase at Oakbank and the Grand Annual at Warrnambool in the same year.

It was Payne's fourth triumph in the race in the past eight years, elevating him to second alongside Ciaron Maher, the legendary Jim Houlahan and Bill Moran with four wins. Kiwi John Wheeler holds the record with five.

The victory capped a roller coaster of a week for star jockey Steven Pateman. It was his third Annual victory and came two days after he won his fourth Brierly Steeplechase. But he has to serve a 10-meeting suspension for indiscretions during that ride.

Payne described Zed Em as a "champion jumper", having won the Von Doussa and Great Eastern steeplechases at Oakbank in the lead up.

Zed Em turned the tables on the Symon Wilde-trained Gold Medals, who won last year. Gold Medals was gallant in defeat, powering home to run second, beaten three lengths.

Payne was delighted with the win but admitted he had been anxious in the lead up and during the run.

"Shocking," he said of his nervousness.

"It's a pretty daunting couple of weeks, you don't want anything to go wrong, if anything goes wrong you're out."

He said he struggled with his anxiety during the marathon.

"It's heart-wrenching stuff watching," he said.

"Still shaking, the revs (heart beat) are up.

"It's a unique race, everything has to go right. It's a pretty heart-wrenching race, every jump you have your heart in your mouth."

Payne said weight was against his champion Kiwi.

"But he doesn't know that," he said.

"He is a champion jumper, he needs a lot of jumps. This track and Oakbank suit him down to the ground so we are very grateful to have this race."

Payne said Zed Em had been completing 10-kilometre training rides up and down hills in New Zealand before owner Kevin Myers sent him to Payne in March.

Payne was full of praise for Gold Medals' gallant run.

"He (Zed Em) was just a bit better weighted today. I thought Gold Medals might get him. I was worried especially when we jumped the last and someone said 'you're home' and gave it the kiss of death."

Gold Medals' trainer Symon Wilde was "rapt" with his jumper's performance.

"These two are genuine top-line 'chasers," Wilde said.

"Zed Em's got an incredible record and Gold Medals is building an incredible record.

"We've been beaten by a champion."

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