The world saw a new Zou Shiming on Saturday night as he made his professional boxing debut. As expected, he beat 18-year-old Mexican Eleazar Valenzuela, but the humble, calm persona that had helped Zou win three Olympic medals - two of them gold - had been replaced with a hyped up version of his former self, and it nearly led to his downfall.

In the lead-up to the fight, Zou was as gracious as ever, patiently answering boneheaded questions from journalists who had no more of an idea about boxing than the rest of us know about winning Olympic gold.

But perhaps the buildup - the month spent training in Las Vegas, the theme song written specifically for this fight, the unheard of $300,000 payday for a pro debut - finally got too much.

It's not often that a four-round flyweight bout tops a strong boxing card, but that tells you everything about the marketing behind Zou. He entered the ring, as countless boxers before him have done, lapping up the applause and punching the air, but for Zou it was out of character. It was almost as if he thought that was what was expected of him, now that he's a professional.

George Foreman, who knows a thing or two about translating Olympic success into a world title, wisely remarked that pro debuts and title fights make boxers do strange things, and Zou's emotion carried over into his performance.

Zou's frantic, windmilling style was, at times, reminiscent of a brawler with little training, not the disciplined fighter who won three World Amateur Championships.

According to all three judges, Zou won each of the four rounds for a unanimous points victory. He was clearly the better boxer on the night, but there were moments when it was hard to tell who was the favorite.

His young Mexican opponent earned every penny of his $15,000 appearance money, about 30 times what he usually gets. But he had been expected to be little more than a punching bag to launch Zou into the big time.

The hope is now that Zou can settle down in his future fights and stick to what has brought him this far already. That includes being humble, because, on Saturday night's evidence, the boxer's bravado act wasn't working.

The bottom line, though, is that the Zou Shiming gravy train is up and running. The question now is: How long will it be before the tracks run out?

The author is a Beijing-based freelance writer. dreyermark@gmail.com