MLB

YANKEES TARGET FIRE-BALLING DEFECTOR

The topic de jour at the All-Star Game is Roy Halladay, being dangled as the big pitching prize of this trade deadline. But the most intense bidding this winter may well be over a mysterious 21-year-old whom many baseball fans have never heard of, an enigmatic phenom whom few outside Cuba have ever actually seen.

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Aroldis Chapman walked out of his hotel and defected earlier this month in Rotterdam, Holland, where the Cuban national team was preparing for a tournament. The 21-year-old — regarded as the best left-handed prospect in the world — has drawn hyperbolic praise from “special” to “a golden arm,” and will touch off a bidding war this winter that will surely include the Yankees, Red Sox and all the usual suspects.

“He’s got a great arm, but he’s not the best in Cuba. That talent’s not translating,” said one high-ranking AL source. “Nobody’s going to sign him and have him go right to the big leagues. He’s going to have to spend time in the minors. But he’s got something other people don’t: a golden left arm.”

That arm delivered a 100 mph fastball at the World Baseball Classic, and Chapman reportedly has hit 102 on the radar gun.

At the moment he’s hidden away in Europe with agent Edwin Leonel Majia. Rumors are he’s in the Netherlands; there’s also talk of Spain. The secrecy adds to the legend of a player seen about as often as Bigfoot, one who has a 24-21 record and 3.72 ERA in Cuba but an arm that portends much more than that.

“I’m very excited to be starting a new chapter in my life and have Edwin and the rest of the team at Athletes Premier by my side to help me realize my dreams,” Chapman said in a release.

And those dreams are lofty.

He’d earlier told Spanish Web site Cubaencuentro: “My goal is to become the best left-handed pitcher in the world.”

While scouts’ opinions on him vary, they agree he has the promise to become an ace. But will he realize that promise? And could it be in New York?

“He’s probably a minimum of six months away. He has to establish residence, clearance,” the AL source said. “He’s probably [getting signed] some time in the summer of next year; maybe they can fast track it to the winter. But I don’t think he’s the major topic of discussion for teams right now.”

Residency could take two or three months, the U.S. Treasury Department clearance and MLB evaluation a couple more. But Chapman could be well worth the wait. ESPN’s Keith Law dubbed him the best lefty prospect he’d ever seen, and estimated he’d sign for between $40 million-$60 million.

One general manager felt the price would be lower than that for Daisuke Matsuzaka, for whom Boston paid a $51 million posting fee and $52 million in salary. That still limits the suitors to big-market teams.

The Yankees and Mets declined comment, but the Bombers will surely make a run at a player with a 102 mph fastball, “plus” curve and “plus” slider.

But with those gifts come red flags. He had a 5.68 ERA in 61/3 innings in the World Baseball Classic, where he appeared immature and had reports surface that he was actually 26. And the resume of Cubans in pinstripes has been dicey — Orlando Hernandez excelled, but Jose Contreras became a $32 million bust.

“We’re flattered by any interest teams may have. However, our primary focus is satisfying the procedural requirements before us, and preparing him for his new life as best we can,” Mejia told The Post.

“We’re currently going through the process of establishing residency for Aroldis outside the U.S. so that he may be declared [a free agent]. Once we’ve completed the necessary processes, we’ll be open to discussing Aroldis with any ball club interested in procuring his talent.”

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The Yanks also are looking for more immediate pitching fixes, and the Toronto Sun reports they’re interested in Ian Snell of the Pirates. The struggling righty is 2-8 with a 5.36 ERA, and was demoted to Triple-A Indianapolis on June 25.

brian.lewis@nypost.com