MLB

Joba must regain lost way

How long ago was it that Joba Chamberlain strode from the bullpen to the mound as if he had materialized magically out of a cornfield in the outfield?

How long since Chamberlain was a phenom who could do no wrong, a can’t-miss-kid in pinstripes with blow-them-away stuff, a charismatic presence and a life story that begged to be told in a movie of the week?

Were we witness to a shooting star?

Or was it all an optical illusion?

The record book instructs us in reality, reminds us that it was only three years ago, in August 2007, that Chamberlain arrived on the scene and created such an immediate impact that he not only became one of those single-name athletes — Joba — but required a set of organizational rules constructed for him to ensure that manager Joe Torre wouldn’t overburden and burn out the kid’s precious 22-year-old right arm.

It seems impossible now.

PHOTOS: INDIANS PITCHER HIT IN HEAD BY LINE DRIVE

If Chamberlain was once a work in progress, it’s now a job to watch Joba pitch. He’s taken his hits over the last two years, some of which was spent in the rotation. Spontaneous joy has just as often turned to spontaneous combustion.

Like yesterday, when the hits just kept on coming in a seventh-inning implosion that, coming relatively soon after two other horrid performances, threatens the structure of the Yankees’ bullpen and serves as a reminder that there is not anyone the organization can rely on to replace Mariano Rivera when the time comes — and it will — for a new closer.

Chamberlain came on with two outs and runners on first and second with the Yankees leading the Indians 10-6 in a game that belonged on a softball field on a Sunday morning.

Four base hits, including two doubles to right, and a walk later, the Indians were ahead 12-10 in a game they had trailed 9-3 after four and would win 13-11. When Chamberlain finally ended the inning with a strikeout, he was booed long and loud by the customers who were more dazed and confused than the pitcher.

Location, Chamberlain said. Location, manager Joe Girardi said. Twelve pitchers combined to throw 402 pitches over 4 hours, 22 minutes, but the 25 delivered by Chamberlain told the tale of a game gone bad and a season turning sour for the Yankees’ designated bridge to Rivera.

“I just missed my spots; that’s the long and the short of it,” Chamberlain said after being rocked for hits by Mark Grudzielanek, Lou Marson, James Donald and Trevor Crowe. “I have to make pitches in that situation.

“My arm felt good, my stuff felt good, it was just bad location. I had to come in and get one out and I didn’t do my job.”

The job, Girardi insisted, remains that of the guy to get the ball to Mo. The manager was resolute despite the fact that Chamberlain has been pounded in three of his last five outings since May 16, allowing 11 runs (10 earned) on 11 hits while walking three over five innings of work.

“People are not going to be bulletproof,” Girardi said. “Joba is our eighth-inning guy. He needs to get it done for us.”

He sure does, for the Yankees have no immediate alternatives. Phil Hughes isn’t moving out of the front end of the rotation to reprise his 2009 role at the back end of the bullpen. Chan Ho Park is an untenable solution.

The Yankees have no choice.

“I know I have to make pitches. If I don’t, that’s what happens,” said Chamberlain, who consistently hit 94 or 95 on the radar gun but left pitches out over the middle. “I’m going to look myself in the mirror and get after it.

“It’s frustrating, but you have to understand to keep it in perspective. You have to have a short-term memory in the bullpen.”

Even if it requires a long-term memory to recall the phenom and phenomenon that was Joba in the late summer of 2007.

larry.brooks@nypost.com