Joba Chamberlain’s rehab assignment began in earnest with the Rookie-level Gulf Coast League Yankees on Tuesday, as the 26-year-old right-hander made his 2012 debut by pitching one inning in the GCL Yankees’ 7-4 loss to the GCL Pirates in Bradenton, Fla.

Facing his first game action since last June 5, Chamberlain didn’t allow a hit or a walk and struck out two of the four batters he faced, but did allow one unearned run courtesy of two errors and a passed ball.

Overall, Joba threw 23 pitches, and while he went to full counts on the first two, he quickly got ahead of the latter two en route to fanning both swinging.

"My heart was racing and it's nice to see somebody up there (at the plate) with the guys behind you," Chamberlain said after the game. "You sweat a little bit more and the adrenaline's going, but I couldn't have been more pleased with my off-speed stuff. Obviously, my fastball command wasn't where I would like it, but as far as velocity and everything that goes along with that with my arm was great."

More importantly than the result, however, is that he seems to have passed the test with a clean bill of health. Joba’s fastball topped out at 97 MPH according to scouts at the game, meaning that the right elbow that underwent Tommy John surgery less than 13 months ago is back at or near 100 percent, and according to a report by Newsday, Chamberlain showed no limp while running wind sprints on an adjacent field after the game, a good sign for the right ankle that was severely dislocated in March.

"That last hitter was perfect for me, just to be able to throw everything and finish with a fastball down and away was exactly where I wanted it to be," said Chamberlain. "Just to feel comfortable and just to be in a game, I mean, really was the biggest thing. So I was very pleased."

Chamberlain is slated to throw a bullpen session on Thursday before making another GCL appearance on Saturday.

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