Joba is not a coward!

NEW YORK - Joba Chamberlain raised his oversized paws, shook his shaggy brown mane and let out a feeble roar. Looking and acting every bit the Cowardly Lion, the big reliever was ready for a scrap Monday.

"Put 'em up! Put 'em up!" he said, playfully challenging Jason Giambi and Mike Mussina. No takers — they were laughing too hard at Chamberlain's head-to-toe costume.

It was rookie hazing day for the New York Yankees, and this well-worn baseball tradition came with a theme: The Wizard of Oz.

So after their 4-1 loss to Toronto, and while the movie's soundtrack played over the locker room speakers, about a dozen rooks slipped into their outfits for the bus ride to the airport and the flight to Tampa Bay.