Michael Spinks. Sugar Ray Leonard. Roy Jones Jr.

The history of those boxing legends provides reason to believe Terence Crawford can overcome what’s viewed as his biggest challenge in fighting Canelo Alvarez on Saturday, Sept. 13.

That challenge is the jump up two weight classes that Crawford (41-0, 31 KOs) had to make to fight Canelo (63-2-2, 39 KOs) in the 168-pound super middleweight division, with Canelo’s undisputed super middleweight title on the line.

Crawford jumped up from 147 pounds to 154 pounds in his last fight. Now he’s leaping again, approximately 14 pounds, and headed into uncharted territory. By contrast, Alvarez is a natural 168-pounder and has fought twice at the 175-pound light weight division.

"In a 12-round fight with that big truck of Canelo just pounding and pounding, it's going to take its toll," trainer Abel Sanchez said.

Trainer Joel Diaz said, "Crawford is a really good fighter. (But) Canelo is a fighter that once he feels that you don't have the power to hurt him, he'll walk you down."

But back to history.

In 1985, Michael Spinks moved up to heavyweight from light heavyweight to fight Larry Holmes, then 48-0. In his previous bout, Spinks had fought Jim MacDonald, who weighed in at 172 ½ pounds. But in that next fight, Holmes weighed in at 221 ½ pounds while Spinks weighed in at 199 ¾ pounds.

Spinks proceeded to beat Holmes by unanimous decision in Ring Magazine’s "Upset of the Year" and win IBF world heavyweight title.

In 1987, Sugar Ray Leonard jumped up a weight class to fight Marvin Hagler at the 158-pound middle weight division. He defeated Hagler by split decision and won the WBC world middleweight title.

In 2003, Jones moved up from the 175-pound lightweight division to heavyweight and faced John Ruiz, who weighed in at 226 pounds and was 38-4-1. Jones weighed in at 193 pounds yet beat Ruiz by unanimous decision.

While naturally bigger boxers might hit harder, Spinks, Leonard and Jones demonstrated the importance of skill. Which is where John Murray, Vice President for Race & Sports at Westgate Superbook in Las Vegas, said Crawford has an edge over Alvarez despite size.

"I think he's the better boxer," Murray said of Crawford. "He's the guy who's never been beat."

This article originally appeared on USA TODAY: Terence Crawford faces weight issue vs Canelo Alvarez. History offers hope.

Reporting by Josh Peter, USA TODAY / USA TODAY

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