LAS VEGAS -- Even as he looks toward the future, Johnny Tapia doesn't try to hide his past.

As he prepares to meet Marco Antonio Barrera tonight in perhaps the biggest fight of his checkered career, Tapia readily acknowledges his mistakes outside the ring.

"It's there every day,'' Tapia said. "I've got a lot of problems. I can mess up tonight or tomorrow. It's always there.''

Tapia's problems have been well chronicled, from his drug use to his hospitalization for depression after trying to commit suicide. They get even more attention this week when a national magazine profiles the struggles of the Albuquerque, N.M., fighter.

"They pick up the old scoops,'' Tapia said. "It's obviously the truth. My past is my past. I don't deny it.''

Tapia hopes his future will overshadow his past Saturday night when he meets Barrera in a 12-round featherweight fight that has a bit of everything except a title involved.

The fight figures to be the toughest of a 56-bout career for Tapia that has spanned 14 years and three weight classes. He's a 4-1 underdog to a fighter generally considered the best 126-pounder in the world.

At the age of 35, Tapia's best days are probably behind him. But, with the struggles he's dealt with outside the ring, beating Barrera might not be so tough.

"You can't count me out,'' Tapia said. "You can never count me out.''

Tapia spent much of his lunch hour Wednesday at a news conference promoting the fight at the MGM Grand hotel-casino, which will not be for a title since the IBF stripped Tapia of his featherweight crown for not following its rules.

But he also talked passionately about himself, his family, and how good he feels about himself today.

"Look at my life now,'' Tapia said. "I've got a beautiful wife who puts up with me and two beautiful kids. I'm kind of hard to live with, but they still love me.''

With scar tissue on his weathered face, Tapia looks every bit a fighter who has been around as long as he has. He started fighting in 1988 and has been at it ever since, except for a three-year layoff beginning in 1991 when he couldn't pass drug tests.

Tapia has won five titles in three different weight classes, a record noted on a large championship ring his wife and manager, Theresa, gave him. But beating Barrera would be the ultimate achievement of a long and turbulent career.

"They've been trying to get rid of me since I first started boxing,'' Tapia said. "But I'm still around.''

Trainer Freddie Roach said that can be largely attributed to the fact Tapia hasn't taken any beatings in his fights, even though he is usually in battles where punches are thrown almost constantly.

"It's not age, it's how many wars you've been in,'' Roach said. "Barrera has been in wars, but Johnny hasn't.''

Tapia thinks that might be just the edge he needs to overcome the odds and beat Barrera, who beat Naseem Hamed and Erik Morales in two of his recent fights.

"Being a big puncher is catching up to him,'' Tapia said of Barrera. "Now he wants to be smarter and last longer in the game. But you can't teach an old dog new tricks.''

Indeed, Tapia should know something about that.