Joba Chamberlain is truly a changed man.

Not only is Chamberlain on a new team for the first time since he reached the majors, he looks completely different. Chamberlain, who debuted with the New York Yankees in 2007, signed a one-year, $2.5 million deal as a free agent with the Detroit Tigers in December.

Fans and reporters at TigerFest needed to look at the name on the card to figure out who Chamberlain was as he signed autographs and high-fived young fans during the event.

"I can have a beard now," Chamberlain said. "I'm excited about that. It's the first year of my life — college (Nebraska), couldn't have any facial hair, and obviously in New York you couldn't. I could have a mustache. Mustaches aren't that cool. I'm not Tom Selleck. It just doesn't work."

Chamberlain was also wearing glasses at TigerFest.

"I wear the glasses because I feel that I look smarter," Chamberlain said. "And I'm too lazy to put my contacts in."

But the biggest physical transformation for Chamberlain is the fact that he's not as big as he used to be.

Chamberlain credits Tigers strength and conditioning coordinator Javair Gillett and his own personal chef, Aaron Young, for helping him lose 15-20 pounds this offseason.

"Aaron is my best-kept secret," Chamberlain said. "You gotta understand that what you put into your body is going to fuel your body. Obviously I've had some injuries here and there. It gets frustrating because you feel like you're doing everything you can, but there's always a little more that you can do. It was definitely a step the right direction for me."

Gillett gave Chamberlain nutritional guidelines that were passed along to Young, who prepares the meals. All Chamberlain has to do is heat everything up.

"He's going to do all my stuff during the season," Chamberlain said. "He's going to write down all that I need to do and hopefully, I can get him to be less busy and come see me for a couple times during homestands to make sure everything gets done. We've already gone over it for spring training and for the year of what we need to do, how we're going to make it."

When asked how much he weighed at his peak, Chamberlain laughed as he tried to come up with the right answer.

"Too big. Too damn big, actually," Chamberlain said. "You go ahead and put that down. It was north of 250."

But Chamberlain said he never reached 300 pounds.

Chamberlain said he's eating more fish than he ever has in his life and he's let go of one of his favorite things.