Only in boxing could you be an undefeated world champion who has won every fight by knockout and also be a mystery. That is part of the odd attraction of prize fighting and also its curse.

These days it is difficult to keep track of the growing list of “champions’’ and harder still to find ways to follow young talent as it rises because, unlike other sports, boxing seems insistent on hiding its light under a basket. Edwin Valero is a case in point.

Saturday night, the Venezuelan-born Valero will fight in the U.S. for the first time since 2003 after having been suspended by the New York State Athletic Commission for a faulty brain scan. Valero has always insisted that was a medical mistake and has gone on to make his case in a profound way. After a 17-month layoff he began to fight again in Japan, Europe and South America and has won 12 straight times, all by knockout. Along the way he picked up the WBA junior lightweight title, a championship he recently relinquished to move up to 135 pounds in pursuit of what he hopes will be a bigger prize – a big money fight with Juan Manuel Marquez or a less valuable stepping-stone match with one of the four other 135-pounders appearing on Saturday night’s “Lightweight Lightning’’ pay-per-view show in Austin, Tx.

Valero, now promoted by Bob Arum but on loan to headline Oscar De La Hoya’s latest promotional venture, cleared every medical test Texas required and was ruled fit to fight despite that five-year-old suspension. This was possible because his license to box in New York had lapsed and on boxing’s odd scales of justice that meant New York no longer had jurisdiction over him.

This was a business decision for Texas as much as a medical one. De La Hoya’s promotional company wanted to headline Valero, in hopes of drumming up future business for him with Marquez, even though Valero remains Arum’s fistic property. If Texas wanted the card it had to find a way to clear Valero and judging by his record it’s difficult to quarrel with their decision.

That may be a break for American boxing fans, who have seen little of Valero for the past half decade but have heard much. If he proves to be as good as the mythology, it should be bad news for 39-year-old former world title challenger Antonio Pitalua (46-3, 40 KO), who has been brought to Austin to be sacrificed for the greater good of the sport.

Pitalua remains a world class boxer but not one likely to be able to stand up to Valero’s kind of clubbing assault for long if the latter is in fact who legend and little else say he is.

In most sports, a rising star like Valero would be well publicized, but in boxing hype sells more than talent, and Valero has had little of the former despite his obvious punching power.

What he remains is a mystery both because of his suspension in New York and his consequent disappearance from the American boxing scene thereafter. That is why he is being showcased by Arum on a De La Hoya card that also includes Joel Casamayor vs. Julio Diaz and Australian Michael Katsidis vs. Jesus Chavez.

He is here to tempt fight fans into believing his power can unseat Marquez, who now holds the WBA and WBO lightweight titles and is considered second only to his nemesis Manny Pacquiao on the pound-for-pound list.

“I’d like to stay here a few years and bring some heat out in this division,’’ Valero said recently. “I want to face the toughest opponents out there. I’d like Marquez to stay in the lightweight division. If Juan Manuel Marquez moves up, vacating other belts, it’s of no interest to me.’’

What remains of interest to Valero and everyone involved with him is that suspension he received in New York on the eve of fighting at Madison Square Garden. While it seems obvious from his performances over the past 3 1?2 years that something was amiss in that test, the implied head injury he had suffered continues to give some people pause.

One of them, however, is not Edwin Valero.

“Every fighter that steps in the ring runs a risk of being injured,’’ Valero said. “I am in no more risk than any other fighter. You know, because of the procedure, because of the surgery that I had – I want to clarify, it was an accident that I had many years ago on a motorcycle. It was very minor. It wasn't what it's played out to be. It (the operation he underwent) was outside of my brain.

“It wasn't that they took my brain out, washed it and put it back in. It was nothing like that. It was a vein that erupted and they took care of it. I've been to doctors all over the world. I've been to Argentina, I've been to Panama, I've been to Venezuela.  I have seen all the best doctors in America.

“I actually saw the doctor that performed the surgery on Marco Antonio Barrera, Doctor Madrazo, and they've all told me the same – that I'm clear to fight. That I'm okay. That I don't run any more risks than any other fighter.

“In December I was in the Philippines and a doctor — the President actually — as a gift gave me an exam and they cleared me as well out there. So I want to repeat that I'm in no more danger than any other fighter, to suffer any more injuries or anything because of what I have. But it could happen to any one of us like it happened a little while ago with the Jesus Chavez- Levander Johnson fight in the past.

“When they pulled my license in 2004 I had to leave in 2005, first to Panama, Argentina and then I landed in Japan. I was there for a few years with my promoter from Teiken Boxing. After a while, living there and raising my family and my kids, it wasn't the ideal place that I wanted there for my family so I spoke to my promoter and said I needed a trainer that would train me personally, that was dedicated to me all the time. Unfortunately in Japan I had a trainer, but he had many other fighters as well.

“We came out to the U.S.; at first I was in Las Vegas with Kenny Adams, but he became a little ill — he has a problem with his heart — and just a situation that happened and it was an emergency change.

“Now I'm here in Los Angeles with “The Professor” Robert Alcazar and I feel very, very happy. We've clicked phenomenally and it's been a great click. We both think alike; we have many same ideas and I think together we can do a lot of good things in boxing.’’

If Valero carries up to the lightweight division the same  devastating punching power he had at 130, he could quickly become the latest in a crowded list of dangerous 135 pounders. Yet as crowded with talent as the division may be, the only man Valero seems interested in is Marquez, who remains the division’s marquee name eve as he plans to move up to 140 pounds to pursue Pacquiao.

Where that would leave Valero is anyone’s guess, although opponents like Juan Diaz, Julio Diaz, Casamayor, Joan Guzman and Katsidis could keep him busy for some time.

For any of that to come about however, Valero first must win back in the U.S. for the first time over five years. On that score, Pitalua figures to offer Valero a challenge for a time, although in his mind not for long.

“I've never said I disrespect him,’’ Valero said of Pitalua. “On the contrary, he's a good fighter. But I know my capacity. I know what I can do, and I know what Pitalua brings. He's a fighter that on the night of the fight he's going to roll. He's going to fall.

“He's too slow for me. I'm too fast, I'm too strong for him. He's a good fighter, but I'm up for bigger and better things.

“I feel very strong at lightweight. Out of my 24 fights about 14 or 15 were at lightweight. In the beginning of my career as there weren't titles or anything on the line, I didn't see a need to drop down to the 130 pound division.

“It was causing me a lot of trouble, a lot of sacrifice, to make 130 pounds. We felt it was time to move up; that's why we vacated the belt and moved up to 135 and gained a little bit of weight. I feel good here.’’

Valero also feels Pitalua looks good standing across the ring from him. While some might see a wily veteran in his 50th professional fight and a guy who carries some dynamite into the ring himself, Valero looks and sees not a problem but rather an opportunity.

An opportunity to make it 25 straight work nights where he knocked off early.

“Antonio Pitalua brings the perfect, perfect style for him to fall and get knocked out,’’ Valero said. “He's perfect for me. Antonio Pitalua is perfect.

“I feel very fortunate to be on this card. I want the whole public to get what they're paying for.’’

What they are paying for is a mystery story, one they hope won’t have a surprise ending.