When Ronnie Shields was asked if he was interested in training Edwin Rodriguez, he didn't immediately say yes.

It's not often that a trainer doesn't jump at the opportunity to work with a highly touted unbeaten prospect, but Shields wanted to watch some film of Rodriguez first to see if he felt they'd mesh.

What stuck out as Shields watched many hours of fight footage of Rodriguez was the lack of defense. But Shields also noticed brief moments when Rodriguez showed extraordinary boxing skills.

"I knew this was a guy I could work with," Shields was saying a few days before the biggest challenge of Rodriguez's professional life, when he meets the great Andre Ward on HBO on Saturday for the WBA super middleweight title. "Edwin had a lot of offense, but he was lacking defense. He was making mistakes he shouldn't have made.

"But what I saw was that he had the ability to do it, and to mix the two. He just needed to work on it and improve on some things."

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And so a little more than two years ago, Shields brought Rodriguez (24-0, 16 KOs) to his gym in Houston and set about rebuilding his game.

Rodriguez had a coming-out party when he faced the tough Donovan George on HBO on St. Patrick's Day 2012. HBO executives loved the match because both Rodriguez and George had reputations as entertaining offensive fighters with defensive issues.

That may not lead to long, successful careers, but it does make for good television.

Shields talked the bout up repeatedly as a toe-to-toe slugfest, but he had a little secret that he kept to himself.

"Edwin's a very smart guy and he was picking things up very quickly, and as we did things, he realized that he could box when he needed to," Shields said. "I challenged him in that fight with Donovan George. I told him, 'Listen, Edwin. You can box this guy and make this an easy fight. That's what you need to do. Go out there and box him.'

"Everyone thought it was going to be this toe-to-toe slugfest, a knockdown, drag-out brawl. But we'd worked on Edwin's boxing so hard, and he went out and boxed the guy beautifully."

It was that performance that announced Rodriguez as a legitimate title contender. He cemented that status in a tournament in Monte Carlo, when he defeated former Argentine Olympian Ezequiel Osvaldo Maderna in March and then knocked out Denis Grachev in the first round in July.

When the opportunity to fight Ward, the 2004 Olympic gold medalist and the best fighter in the world not named Mayweather, Rodriguez never hesitated.

"I feel like I've been ready for a while now," Rodriguez said. "… I've been asking for this fight for a while now. This is my time. I'm ready."

But in Ward, he's facing a rare talent, and a guy who, as great as he is, seems to be improving. Ward (26-0, 14 KOs) is coming off an impressive 10th round stoppage of Chad Dawson last year.

Ward has had a reputation as a guy who is tough to hit, though Shields said, "I wouldn't put him in Floyd Mayweather's class in terms of defense, because no one has a defense like Floyd Mayweather."

But Ward's offense has become more effective, and he expects it to be even better because he had a torn right rotator cuff that bothered him for years surgically repaired.

Rodriguez is under no illusions about what he faces, and said there is no simple way to win. All of the lessons he's learned from Shields will come into play Saturday.

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