In a week where yearlings are being sold for up to $2 million, Newcastle trainer John Bannister is just happy to be a part of a major race at The Star Championships at Royal Randwick with his $3000 purchase Poseidon Ruler.

Bannister feels a little like he's been thrust into Saturday's $500,000 Polytrack Provincial-Midway Championships Final (1400m) at the last minute as Poseidon Ruler was destined to be an emergency for the race having run third in one of the qualifying races.

But, ironically, his former boss Kris Lees didn't accept with one of his qualified horses and the four-year-old comes off the bench for a shot at a race worth more than 160 times his purchase price.

"I'm looking forward to the day, I just get a bit nervous hoping he runs well,'' Bannister said.

"He's never put in a bad run since we've had him. Half of me was happy and the other half was thinking it's a bit hard for him at the moment.

"It's a bit stressful. Three weeks ago he was a Class 1 country horse and now he has to step up. He's probably six or eight months away from being a proper horse, he's still learning."

The 47-year-old self-described hobby trainer only has six horses on his books, one less than Lees has lining up in the Provincial-Midway Final, and while he trains at Newcastle he has a 100 acre property at nearby Branxton where his horses are housed.

Poseidon Ruler has proven himself to be a shrewd purchase.

The gelding was one of about 20 horses that was due to be exported but remained in Australia through the early stages of the Covid pandemic and Bannister snapped him up for owner Sean Donza from a dispersal sale.

"I rang the owner up and said you should buy this horse, he was a nice walking horse, so we got him for three grand,'' he said.

"So whatever he does is a bonus."

He's so far won just over $80,000 and sixth is his worst finishing position in 15 starts.

The Polytrack Provincial-Midway Championships series was a bit of a pipe dream for Bannister, it was a loose aim when Poseidon Ruler started his preparation but at the time he'd only won the one race at Scone.

After back-to-back wins at Muswellbrook and on Newcastle's Beaumont track in the space of 11 days in March he elected to have a throw at the stumps and send him into a qualifier four days after his latest win.

He ran third on a heavy track behind Barossa Rosa and Grande Rumore. They'd tried and Bannister was satisfied with that.

"The owner wanted me to put him in a heat but when he spelled he was a few weeks behind because he had a bug,'' he said.

"My plan was to run in Wild Card but we weren't sure if he would get a run so after he won at Newcastle we decided to back up.

"He ran third and that was pretty good. I wasn't expecting him to run top three, he was miles up in grade, but he kept stepping up."

Poseidon Ruler is one of the outsiders on Saturday, he was $81 with TAB midweek, but Bannister points out he's finished in the top three in 13 of his 15 starts so whatever he may lack in class he makes up for in honesty.

But he's realistic.

"He'll run well, I just don't know if he has the class of Never Talk and Rustic Steel,'' he said.

"They might be a bit better grade than him. But, if you're not there, you've got to be in it. He'll go through the heavy but he's probably better on top of the ground."