MLB

Joba’s shaky start puts playoff spot in limbo

Joba Chamberlain’s regular season is mercifully finished. Any chance the Yankees give him an October vacation as punishment for a job not-so-well done?

Last night, the erratic right-hander lit a stink bomb and lobbed it high above the pitcher’s mound at the Stadium, bringing additional cloudiness to his status for the ALDS and potentially beyond.

The Yankees were denied victory No. 103 in a 4-3 loss to the Royals, after Chamberlain allowed three earned runs on seven hits and four walks over 3 2/3 innings.

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“He pitched out of a lot of jams, but we didn’t get the length from him that we wanted,” manager Joe Girardi said. “It was not a good start.”

It’s been a no-brainer for weeks that barring an injury Chamberlain will be omitted from the Yankees’ ALDS rotation — CC Sabathia, A.J. Burnett and Andy Pettitte will handle those honors. But it shouldn’t be considered an automatic that Chamberlain earns a bullpen job. Not after posting a 7.15 ERA in September while frustrating the Yankees, particularly in the first inning of starts.

Nor should it be a given that Chamberlain will get an ALCS start should the Yankees advance past the first round. Though Chad Gaudin never will be confused with Cy Young, he has been more dependable than Chamberlain and could be a consideration for postseason duty, both in the bullpen and ultimately starting an ALCS game.

“If they tell me to fold towels, I’ll fold towels — I don’t really care,” Chamberlain said. “I’ll do anything to win on this team.”

Chamberlain’s early-inning woes continued last night with two walks in the first inning before Brayan Pena delivered an RBI single. It was the fifth time in his last seven starts that Chamberlain allowed at least one run in the first inning. His first-inning ERA this season is 5.58.

Girardi will wait until next week before deciding on Chamberlain’s fate. The manager admitted it could be a crapshoot putting Chamberlain in the bullpen, though the right-hander dominated as a reliever earlier in his career.

“I can’t guarantee that when you put a guy in a [relief] situation, he’s going to revert back to his old form,” Girardi said. “But he does have a lot of confidence coming out of that gate.”

Chamberlain heard a mixture of boos and applause as he departed in the fourth inning after surrendering an RBI single to Pena. Chamberlain, who threw 91 pitches, completed his regular season with 156 1/3 innings pitched, keeping him at less than 160 for the year as the Yankees had wanted when they instituted the 2009 Joba Rules.

The Yankees got a leadoff homer from Derek Jeter to make it 1-1, before Chamberlain walked a tightrope to escape the second inning unscathed, after loading the bases.

In the third, Alberto Callaspo doubled leading off and scored on Mark Teahen’s single. Josh Anderson’s single leading off the fourth started another scoring rally against Chamberlain. After Anderson stole second, Mitch Maier sacrificed him to third and Pena stroked an RBI single. Alfredo Aceves replaced Chamberlain and got the inning’s final out.

John Buck’s RBI triple against Sergio Mitre in the seventh produced the go-ahead run for Kansas City after Nick Swisher’s two-run homer in the fifth had tied the game.

“I didn’t have fastball command at all,” Chamberlain said. “It could have gotten a lot worse than it was.”

mpuma@nypost.com