If the Yankees weren't about to hand the job to him on a silver platter, which they wouldn't, Chamberlain made it his mission to prove that Joe Girardi should be giving him the ball in those key situations once again.
"That's the first thing that came into my mind," Chamberlain said. "Knowing that I've been in that situation before, but also knowing that I still had a lot to prove. It's not just going to be handed to me; we've got a lot of guys throwing the ball well.
"I had to go back out there and prove myself again in that role. There was no time to be disappointed, because I had to prove to myself that I could still help this team on the other side."
Chamberlain seemed like a natural fit for the role in Tuesday's 7-3 win over the A's, hurling 1 1/3 scoreless innings of relief with three strikeouts to help preserve Javier Vazquez's first victory of the season.
It must have been enough of an audition for Girardi, who finally seems ready to declare that Chamberlain has been anointed as his eighth-inning reliever.
"I think he's done what most of us expected him to do," Girardi said. "I think he's enjoying himself and what he's doing. It's nice when guys have roles and you can turn to them, and when the phone rings they know it's them."
Girardi prefers to keep his bullpen roles fluid, mostly because he likes to stay away from using pitchers three days in a row and anticipates that there will be days when someone else is asked to fill in. But Girardi noted that he likes the way Chamberlain has gone about his business, which is as close as a definitive statement as he has offered.
"The thing about Joba is [that] I don't want to push him too fast," Girardi said. "He's adjusting to going back-to-back and those sorts of things. That's why I haven't really said, 'Oh, this is going to be my eighth-inning guy.'
"We have to see how guys respond a few times going back-to-back and how they physically feel. You have to be careful that you don't crown someone before it's time."
Chamberlain entered Tuesday's game in the seventh inning, inheriting a high-pressure situation with the bases loaded and the tying run at the plate, and he escaped by striking out Kevin Kouzmanoff put an end to the Athletics' latest and greatest threat of the evening.
"One bad pitch to a great hitter could tie the game," Chamberlain said. "To bring me in that situation -- bases loaded -- you've got no room for error. There's no free base. To have that confidence to put me in that position is a good feeling."
While the Yankees have made it known that Chamberlain won't return to the starting rotation in 2010, the right-hander has not closed the door on the idea that he might someday log another big league start. But for now, he is a reliever, and that is where his focus needs to be.
"I can't look at what it's going to be," Chamberlain said. "I take it one day at a time. It's one thing where you've got to embrace your role and go with it. You can't look back, you can't look ahead. You've got to take it one pitch at a time and continue to go from there."