New York Yankees right-hander Joba Chamberlain didn't get much defensive support, but he made a good impression Tuesday in his first rehab appearance.

Working as the starter for the Yankees' rookie-level Gulf Coast League affiliate, Chamberlain got the Pirates' leadoff man to hit a grounder on which two errors were committed, leaving the batter at second base. The next batter grounded out, advancing the runner to third, and a passed ball scored an unearned run. Chamberlain struck out the final two hitters in his lone inning.

It was Chamberlain's first action in an official game this year. He began spring training rehabbing after undergoing Tommy John surgery in June 2011, and then he severely injured his right ankle in late March while playing with his son on a trampoline. He underwent ankle surgery.

Chamberlain began throwing bullpen sessions a month before he finally began his rehab assignment.

The absence of the 26-year-old reliever has hampered a Yankees bullpen that is also missing closer Mariano Rivera, out for the year after injuring his right knee in April.

Last year, Chamberlain went 2-0 with a 2.83 ERA in 27 appearances before he was shut down with the elbow injury that led to surgery.