Shohei Ohtani is on the brink of becoming baseball's first $500 million man.

The Japanese phenom is a superstar as big as they come, having spent his career rewriting a century of conventional wisdom about what is — and isn't — possible in baseball.

The 28-year-old is simultaneously one of the best hitters and one of the top pitchers in the world, a combination no one has even come close to since Babe Ruth more than 100 years ago.

"You might never see anything like this again," former Major League Baseball (MLB) pitcher Warwick Saupold said.

That historic talent is why teams in North America are clamouring to hand Ohtani one of the largest contracts in global sporting history, with many experts predicting he will blow past the MLB record of US$426 million and end up signing for more than half-a-billion dollars.

That would put him in the rarest of company around the globe, with Lionel Messi the only athlete to ever be handed a US$500 million guarantee.

Australians fighting for chance to face Ohtani

It's an awfully long way from the fields where many of Australia's best baseball players ply their trade.

Some of those players are fledgling professionals trying to fight their way through the gruelling minor league system in the United States for a shot at the big time, the rest are part-timers — balancing baseball commitments with full-time work.

But those two worlds are about to come crashing together.

Ohtani is the headline attraction for Japan in its roster for the premier international baseball tournament, the World Baseball Classic, this March.

And with Australia drawn to play against Japan in Tokyo, it has presented a once-in-a-lifetime opportunity to go up against one of the best the sport has ever seen — in their own backyard.

"It'll be a crazy experience," West Australian catcher Alex Hall said.

"Just to see him in person would be crazy, to face him would be even better — no matter the result, I can say I've done it."

It's a perspective widely shared among Hall's prospective Australian teammates.

"It'll be one of those memories you never forget," outfielder Ulrich Bojarski said.

"He is one of those unicorns in the game … it's really exciting, getting to face one of the best players in the world."

Aussies bracing for fan frenzy

Bojarski and Hall are among the dozens of players around the country waiting anxiously to find out if they will get that chance, with the final Australian team set to be named early next month.

That group of hopefuls is competing against each other during the Australian Baseball League (ABL) season, their last chance to impress the coaching staff before that final call is made.

The fledgling ABL takes place mostly in outer-suburban fields that draw anywhere from a few hundred spectators on a quiet day, or closer to 1,500 for a big game.

But it will be a very different environment waiting for those lucky enough to make the Australian squad.

Tickets for the games at the Tokyo Dome, a 55,000 capacity venue in the centre of the capital, sold out within minutes.

With Ohtani playing in the United States with the Los Angeles Angels, since leaving the Hokkaido Nippon Ham Fighters after the 2017 season, it's a rare chance for the Japanese public to watch one of the country's biggest celebrities in person.

And the Australians are bracing for a frenzied crowd.

"It is unlike any other atmosphere," Australian captain Tim Kennelly said.

"We know that they're going to be loud and it's going to be crazy, we're just lucky we get to take part in it."

The preparation 'juggling act'

Kennelly is one of the many athletes balancing career commitments and tournament preparations, working as a full-time firefighter in WA on top of his Perth Heat and Team Australia commitments.

"There is a lot of guys in the same boat as me, we just put in the work whenever we can and then get out there and compete against the best in the world."

It may sound like a lop-sided proposition — with a Samurai Japan side featuring a host of Major League talent, led by Ohtani, on top of local superstars such as Roki Sasaki and Munetaka Murakami, seen as one of the tournament favourites.

But Australia has come close to causing an enormous upset in a couple of their recent meetings, leading Japan for several innings when the two teams faced off in both the 2017 World Baseball Classic and 2019 Premier 12 tournaments.

And this year, they believe they can go one better — despite the presence of Ohtani.

"On paper they obviously have a really good team compared to us," Kennelly said.

"But it's nine innings — we have to be on top of our game and hopefully we can get on top of them this time."