Testashadow may not be the best horse Gary Portelli has trained but he has earned his place near the top of the stable's hierarchy.

The eight-year-old has won more than $1.4 million for his owners Elite Thoroughbreds during a career that began almost six years ago.

He has also earned a shot at Saturday's $1 million The Gong (1600m), the richest race ever run at Kembla Grange.

"He is an owner and a trainer's dream," Portelli said.

"He's sound. He does his work and he comes off the track in the mornings like a three or four-year-old and eats up.

"And then he does it all again the next day."

Portelli also has Testashadow entered in the 1600m-benchmark 88 race on the program and barrier draws will determine where he runs.

"He can't win a million dollar race against these horses from an outside barrier but he can run a place in a million dollar race from a good draw," Portelli said.

"I will accept in both races and if he happened to draw badly in both then we would save him for another week and maybe go back to Brisbane with him."

A Group Three winner and multiple Group placegetter, Testashadow won the 2017 Magic Millions Cup and on a more recent trip to Queensland finished an unlucky third over 1600m at Eagle Farm in September.

At his latest start, Testashadow was fourth in the Listed Ladies Day Cup at Hawkesbury on November, less than half a length behind the winner Cellarman.

Portelli also entered Saturday's Newcastle winner Strome in The Gong but she will be saved for another day.

"She was impressive at Newcastle but she won't run on Saturday," Portelli said.

"We'll keep monitoring her and there is a benchmark race in three weeks and if she wins that we might look at The Villiers.

"She just keeps stepping up and her sectional times at Newcastle say that.

"They were the best of the day and she could go to another level yet."

Group Two Shannon Stakes winner Mister Sea Wolf is the topweight with 59kg for The Gong with Testashadow to carry 53kg.

Group One-winning mare El Dorado Dreaming is the TAB's $5 early favourite ahead of Luvaluva and Star Of The Seas at $6.