MLB

Prior makes Yankees debut

Mark Prior Seeking some relief.

Mark Prior Seeking some relief. (N.Y. Post: Charles Wenzelberg)

TAMPA — The guy who was going to be the first $150 million pitcher had a shutout working with one out in the eighth inning.

It is a piece of the story that becomes obscured over time. Forgotten in Luis Castillo’s foul flyball. Moises Alou’s anger. Steve Bartman’s unwanted fame. And the Cubs’ enduring misery.

At the moment the ball left Mark Prior’s right hand, he was, in Castillo’s words, “the best pitcher in baseball.” In fact, speaking from Mets camp, Castillo added: “We wouldn’t have admitted this at the time, but it was true — we honestly didn’t think there was any way we could beat him.”

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That was totally understandable. Prior had played on the 2000 U.S. National Team with, among others, Mark Teixeira and Ryan Howard, and Teixeira remembered: “He was the best player on the team and, really, it wasn’t close.”

Prior was selected second overall in 2001 by the Cubs and “you didn’t have to dream on him,” Yankees scouting chief Damon Oppenheimer said. “He already was the full package of size, ability, know-how.”

Prior reached the majors at 21 in 2002 and his pitching coach then (and now), Larry Rothschild, recalled: “He was as good as any young pitcher in the game.”

In his first full season, 2003, Prior finished third in the Cy Young voting and threw a two-hit complete game to outduel Atlanta’s Greg Maddux in NLDS Game 3.

“He just dominated us out of the playoffs,” then Braves center fielder Andruw Jones said.

So when he released that pitch on Oct. 14, 2003 — Juan Pierre on second for Florida, the Cubs up 3-0 and five outs from their first World Series appearance since 1945 — Prior was at the top of his powers. He had turned 23 one week earlier. He was going to be the NLCS MVP after also winning Game 2. But Castillo lifted a foul ball. Bartman reached up, obstructed Alou from a potential catch. The beginning of the end for the Cubs was set in motion — and, really, for Prior, as well.

Prior lost the first two months of 2004 with an Achilles tendon injury. He was good, but not $150 million great in 2005, and out of the majors for good after a 1-6, 7.21 ERA in 2006. His shoulder was a mess. Was it the remnants of the fall after colliding with Atlanta’s Marcus Giles during the 2003 season? The heavy workload at a young age orchestrated by then Cubs manager Dusty Baker? Prior’s motion — known as the “Inverted W” — in which, among other things, the pitching elbow raises above the shoulder during the backswing? Or simply genetics? Whatever the cause the 95-mph-plus fastball, nose-to-toes curve and GPS-like location vanished.

“There was nothing tricky,” said Tino Martinez, who was 1-for-14 as a Cardinal in 2002-03 versus Prior. “He was fluid and powerful and, wow.”

The Mark Prior who threw batting practice before yesterday’s full workout has a modified, lower arm angle. He now pitches at 88-92 mph with a slurve and a split he began working on last summer. At 30, Prior should be in his prime, should be in the midst of that $150 million contract.

Instead, the Yankees signed him to a minor league deal after liking what they saw late last year. Prior is trying to make it as a reliever. Even he says he “is a realist,” which means he almost certainly must go to Triple-A to prove he can stay healthy and still get hitters out.

“Once I decided to give this one more try after the 2009 season, I decided it was no looking back, no living in the past,” Prior said. “I know where my place was supposed to be and what my ability was. But I am here now.”

Prior is part of the Used-To-Be-All-Stars at Yankees camp with Jones, Eric Chavez, Freddy Garcia and Bartolo Colon. And he also is the cautionary tale about young pitching at a moment when the Yankees organization is in a giddy frenzy over Manuel Banuelos and Dellin Betances, in particular.

But Prior concentrates neither on his past nor anyone’s future, including his own. He faces the daily battle of tolerable shoulder discomfort, a new job, an adapted delivery. The guy who made his first major league pitch to a catcher named Joe Girardi on May 22, 2002, now wants to play for Girardi. Not as the guy who pitched to Castillo or should have been the first $150 million pitcher, but as a guy who still loves the game. Today. Just today.

“It is not the career path I envisioned, but it is the career path I am on,” Prior said. “So be it. No regrets.”

joel.sherman@nypost.com