Steven Nelson knows better than anyone how well Terence Crawford deals with super middleweights and even heavier fighters.

One of Crawford’s closest friends has sparred countless rounds with the four-division champion since Crawford competed in the lightweight division. Nelson has boxed at light heavyweight and super middleweight since he made his pro debut nine years ago, yet that never deterred the smaller Crawford from going at it with him in the gym.

Nothing Crawford accomplishes in their sparring sessions surprises Nelson anymore. The Omaha, Nebraska native is certain, however, that Crawford’s power and aggression with catch boxing’s undisputed super middleweight champion off guard September 13 at Allegiant Stadium in Las Vegas.

“People think he’s gonna get in there and just run the whole fight,” Nelson told The Ring. “[They] think he’s gonna move around, box and move around, move, move around. Like dude, I’m just looking forward to … seeing what their excuses are, seeing what they say.”

Crawford’s critics contend he won’t be able to take Alvarez’s power in their 12-round, 168-pound fight for the Mexican icon’s Ring, IBF, WBA, WBC and WBO titles. They also doubt Crawford will be able to hurt Alvarez, whose granite chin has been one of his most consistent strengths in almost 20 years as a pro.

Nelson (20-1, 16 KOs), who will face Cuba’s Raiko Santana (12-4, 6 KOs) in a 10-rounder on the Alvarez-Crawford undercard, laughs and reminds them whenever he gets the opportunity that they’re misinformed.

“Every time Bud steps up,” Nelson said, “and fights new guys, since he was at, shoot, 135, 140, it’s always, ‘Oh, I don’t know how he’s gonna be able to take this pressure. This guy’s bigger.’ It’s always that. But since I’ve known Bud, he’s always got in there with bigger guys and made statements and ended up being the bigger man. I’ve seen it, I’ve felt it.

“I’m a bigger guy and we’ve sparred countless rounds, and I’ve seen him in there with so many people, including Lester [Martinez] and everybody, and that’s never gonna be a factor. It’s not gonna be a problem. Bud has always been a heavier guy, but he’s always had to go down, hold his weight. He’s never had a chance to grow.”

Crawford’s 14-pound jump up in weight – from the junior middleweight limit of 154 to the super middleweight maximum of 168 – didn’t exactly stun Nelson. And not just because Crawford (41-0, 31 KOs) will make a career-high purse for challenging Alvarez (63-2-2, 39 KOs) in a fascinating fight Netflix will stream worldwide.

Though Omaha’s Crawford, 37, has competed above the 147-pound welterweight limit only once, he has tested himself for many years in the gym against fighters as big or bigger than Alvarez. Guadalajara’s Alvarez, 35, has competed as a super middleweight or light heavyweight in each of his 12 fights since May 2019.

“Even when Bud was at 135, 140, he was always sparring bigger guys,” Nelson said. “When I say bigger guys, I mean me – my size and bigger. And not just me, people in my weight class, people bigger than me. Bud is so competitive, anybody comes in the gym he’s gonna challenge him.”