ATLANTIC CITY — Unbeaten heavyweight prospect Seth “Mayhem” Mitchell escaped early trouble in the first round of his fight with Chazz Witherspoon, won the second round, dropped his rival with a powerful third-round left hook and later pinned and pummeled his fellow American hopeful against the ropes to forced referee Randy Neumann to step in and wave an end to the bout before a raucous crowd at Boardwalk Hall.

The resulting TKO victory, which came at 2 minutes 31 seconds of the third round, improved Mitchell’s record to 25-0-1 with his 19th knockout. Witherspoon dropped to 30-3, with 22 knockouts.

“I’ve been working on my right hand. I knew that he was coming to fight. In the heavyweight division, it only takes one shot. I’m going to be honest, I was a little nervous for this fight,” said Mitchell.

“He’s got a lot of experience, and I saw in his eyes that he was coming for me. But I never stopped using my body shots. They were slowing him down, and he had no defense for them.”

Mitchell was wobbled, in trouble, and, admittedly, in danger of going down in the first round after Witherspoon caught him with a succession of blows that caused his legs to do a dance as Mitchell held on to blunt and smother his rival’s attack.

“Did I get hurt? He dictated with his jab. It wasn’t a real powerful jab, it was just a real pestering jab. I thought that I was out of range, and I stayed at the end of his jab and let him get on track. They say when you allow somebody to set up their lead hand, their powerful hand is always there for the kill. He hit me with the right hand. It was an equilibrium shot,” said Mitchell.

“Those shots throw your equilibrium off. I did the stanky leg a little bit. But I was able to recover. I’m not too prideful to hold on. I’m not stupid and stand there and fight when you’re dazed. He saw that he hurt me, came in for the kill, and I just grabbed him and held on. Once I got out of the first round, I knew I could make the adjustments.”

Trainer Andre Hunter told Mitchell to “basically grag him and tie him up,” adding, “after that, get your legs back together. I wasn’t worried about him trying to get it back too soon, because I knew that it could be a long fight.”

Mitchell did just that, crowding Witherspoon and also digging to the boddy in the second round.

“I knew that I couldn’t let him dictate with his jab as he did in the first round. I had no cobwebs in me after I got out of the first round. I was clear. My head was clear. I knew that I had to go out there and dictate with my jab and not let him be the leader and to attack the body. Once I did that, things started to fall into place,” said Mitchell.

“His jab in the first round was like a knat. I couldnt’ get it out of my face. I know they say that if you kill the body that the head will follow, so I was able to hit him with some good straight rights to the body. That was part of the gameplan, and I think that slowed him down. I knew that Chazz could box, but I also knew that once he got into a firefight, he would be open for a lot of shots.”

Mitchell drew Witherspoon into a war for the third round, where he dropped him with a solid left hook that followed a right hand. Witherspoon rose, but Mitchell pressed his advantage, driving the Philadephia-based fighter to the ropes, where Neumann stepped in and separated them.

“I knew that I had it in me. The dog had not been brought out of me. If I get knocked down, I can get up. Some fighters, they get knocked down, and they have some quit in them. I have not an ounce of quit in me. Not saying that I can’t lose, but if I can get up with any fiber of my body, then I’m going to fight. So when you come to see Seth Mitchell fight, win lose or draw, it’s going to be a fight,” said Mitchell.

“I was confident that I was going to finish him in that round or in the next round, because I saw the look in his eyes and I saw that my power was really affecting him. I was dodging and weaving when he was letting his hands go, and I came back with the left hook and that’s what we looked at and studied on tape and it worked out perfectly tonight.”

Considered America’s best hope at ending the country’s drought of champions in the division, Mitchell, of Brandywine, Md., fought Witherspoon on the undercard of the rematch between RING light heavyweight champ Bernard Hopkins and Chad Dawson, the latter of whom dethroned Hopkins by majority decision in an HBO-televised event.

“I thought it was a terrific performance. A bit scary there in the beginning, but he made adjustments and he turned it around and got a big knockout,” said Golden Boy Promotions CEO Richard Schaefer.

“It’s a learning experience for Seth, and I think that he’s doing very well. He’s passing with flying colors. We want to try to get him back as soon as possible. It’s a learning experience.”

Mitchell, 29, was coming off an HBO-televised second-round knockout of Timur Ibragimov (30-4, 1, 22 KOs) at The Washington Convention Center last December.

Mitchell earned his 10th consecutive stoppage and his 23rd consecutive victory against Witherspoon, who had reeled off four straight knockout wins since, himself, being stopped by southpaw contender Tony Thompson in the ninth round in December of 2009 at Boardwalk Hall.

“I got a little excited after I had him hurt, but I never got back to fighting smart. He dealt with the adversity great,” said Witherspoon. “I started fighting a stupid fight after I got him hurt. I was just looking for the knockout. He has great athletic ability.”

The Ukrainian Klitscho brothers, Vitali and Wladimir, dominate the division, but even they have mentioned Mitchell as perhaps the United States’ best heavyweight.

“I don’t think that we need to go and chase the Klitschkos. I just don’t think that makes much sense. You keep on building him. This is not about let’s go for a pay day,” said Schaefer.

“This is about really building a heavyweight champion here in the United States. That’s the plan. The plan is not go go and get a big payday fighting over in Germany.”

Golden Boy Promotions’ President Oscar De La Hoya agreed.

“The Klitschkos have mentioned Seth Mitchell in the past as a possible opponent, so that’s obviously a good sign, because the Klitschkos are willing to face the very best in the heavyweight division, so they have their eye on Seth Mitchell. We do have a plan for Seth Mitchell. We have discussed future opponents. We have to go back to the drawing board,” said De La Hoya.

“Monday, I’ll sit down with [Golden Boy Promotions matchmaker] Eric Gomez and we’ll sit down with Richard. I’ve thrown out a couple of names out there that I really like. We’ve discussed a possible fight with Michael Grant, for instance, who is a big, solid heavyweight at 6-7 or 6-8 with a great record. It’s just a matter of sitting down with Seth’s team and nailing down a guy.”

Lem Satterfield can be reached at [email protected]