LAS VEGAS -- David Tua is bored talking about Saturday's fight with Chris Byrd. If he wins, though, it will be a different matter.

That's because the winner of the heavyweight bout becomes the mandatory challenger for IBF champion Hasim Rahman.

Billed as "Mandatory War," the fight is a match between fighters with much different styles -- Tua is the puncher and Byrd the boxer.

Even Byrd, a former WBO heavyweight champion from Flint, Mich., said the bout is a classic contrast of styles.

"You've got pure boxer facing puncher," he said Thursday at a news conference.

Tua, the IBF's No. 1 contender, is almost a 5-1 betting favorite, but the second-ranked Byrd said the fight at the Cox Pavilion at UNLV is a great opportunity for him.

"Tua, I respect as a great boxer. I can't tell you how excited I am for this bout to happen," said Byrd (33-2, 19 KOs). "I got to fight my way to the title."

Tua (38-2, 33 KOs) said he has been in boot camp-style training for the fight. He showed up Thursday in fatigues and a camouflage beret hiding his usually spiked hair.

Tua's co-manager, Kevin Barry, said the New Zealand native is in the best shape of his life and promised boxing fans will see a different, more dedicated fighter.

"I'm bored of talking about the fight," Tua said when he finally got up to talk.

Later, Tua said he meant no disrespect to anyone, but "I just want to fight. I've done my own work. There's nothing else to do but fight. The homework is done."

Among the fights on the undercard Saturday, Augie Sanchez of Las Vegas (28-2, 25 KOs) meets Australian Robbie Peden (19-1, 10 KOs) for the NABF/USBA featherweight championship.