From Mike Vorkunov:
Joba Chamberlain will make a rehab appearance in Trenton today with the Yankees' Double-A affiliate. He will enter into the game with two outs in an inning then stay in to pitch the following inning, in hopes of simulating what he would do at the major-league level. He has been placed on a limit of 30 pitches in an inning.It's also mentioned in the article that Trenton manager Tony Franklin was unsure how long Joba would be with the team, but it's possible Joba could remain there until Tuesday.
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“Yeah, I feel like I’m ready,” Chamberlain said Friday. “Obviously, physical part is over. Now it’s just the mental part of getting in a routine and trusting your pitches and trusting you can get guys out.”
Check back later for an update on his outing.