TAMPA, Fla. — Joba Chamberlain doesn't worry about whether he'll wind up in the New York Yankees' rotation or the bullpen.

A starter in the minors, Chamberlain became Mariano Rivera's primary setup man during the final two months of last season. The Yankees say the 22-year-old eventually will be a starter, but that he will have an innings limit this year and could start in the bullpen.

"We've approached it in a great way. We're going to go in the beginning and understand there's an innings limit, and I know that," Chamberlain said today. "I'm excited to have a new challenge this year."

Chamberlain enters spring training along with two other heralded young pitchers: Phil Hughes and Ian Kennedy. The Yankees are relying on youth more than in recent years as they try to dethrone the World Series champion Boston Red Sox.

"They won. Now, it's up to us to take that away," Yankees catcher Jorge Posada said. "They've done things right. They're a good group of guys. They've got some youngsters that played good toward the end of the season. Obviously, they are the defending champions. There's no question, we are following them."

Chamberlain will work with the starting pitchers during the early part of spring training, even if he begins the season in the bullpen. Last year, Chamberlain worked under strict pitch and innings limits, which came to be known as Joba Rules.

"This game is definitely a marathon, not a sprint, and I understand that," Chamberlain said. "Last year, it was kind of frustrating, having the rules, but you understood what it was about. I understand the work load and what's going to go on, but this is going to be my first go around, so I've got to be patient and learn and understand that I've got to ask questions as I prepare myself for a full season in the big leagues."

Chamberlain has been throwing off a mound for the past month at the Yankees' minor league complex. The on-field success has changed his off-field life, which includes being recognized more in public and invitations to baseball events.

"I definitely got some frequent-flyer miles, I'll tell you that much," Chamberlain said with a smile. "It's just the opportunities that came, and the people that I got to meet was great. If you don't perform on the field, you don't get to do all that great stuff and enjoy yourself in the offseason. It was definitely an honor. Hard works pays off, but you've got to come back and work even harder so you can have that much fun next year."