But skipper Joe Girardi is still impressed with the right-hander, whose 2011 season was cut short in June due to Tommy John surgery. While working his way back from the injury, Chamberlain also suffered an open dislocation in his right ankle -- just prior to the season -- that required surgery and forced him to miss four months.
Chamberlain has allowed at least one run in each of his four appearances and walked two batters over 4 1/3 innings of work. The sample size is too small to get a good indication of his performance, but Girardi has noticed some things along the way.
"I've seen improvement each time. I think his stuff has been a little bit more consistent," Girardi said. "His slider has been more consistent and I think he will get better as time goes on."
Chamberlain is throwing his curveball and slider around the same amount he did last season, according to Fangraphs.com. The only real difference to date is that he has been throwing his fastball less and throwing a chanegup at a career-high rate.
As for his fastball, it has averaged 94.1 mph, which is a slight tick above his career norm.
Girardi said it's important to get him more innings but balancing how he does that, pending on the game situation, will be the difficult part.