Savannah Marshall is considered the superior puncher in her showdown with Claressa Shields.

The undefeated Shields has definitely fought a higher level of opposition, yet she has won only two of her 12 professional bouts by knockout. Marshall, meanwhile, has stopped 10 of her 12 pro opponents inside the distance.

Shields respects Marshall’s power, but the three-division champion predicted during a recent conference call that she’ll surprise Marshall with her own strength when they square off September 10 at O2 Arena in London.

“She gotta feel this pain,” Shields said. “If I can get her out earlier, I will. But I know that I think she’s sturdy. And she do have a little bit of size on me, as far as height. But I think she’s gonna be very, very shocked at how strong I am and how hard I punch, especially going into the later rounds.”

England’s Marshall has gone 10 rounds, the maximum allowance in women’s boxing, only once since he made her pro debut in August 2017.

Each of Shields’ past eight fights, all championship matches, have gone the 10-round distance. The two-time Olympic gold medalist hasn’t recorded a knockout since she stopped Nikki Adler in the fifth round of their August 2017 bout in Detroit.

Shields would love to end her knockout drought against Marshall. More than anything, though, she wants to avenge her lone loss as a professional or amateur boxer by beating her rival in their middleweight title unification fight.

“I’m just happy that I’ll be able to show why I reign, you know, ‘GWOAT,’ you know, why I’m the greatest woman of all time,” said Shields, who lost a 14-8 decision to Marshall at the 2012 AIBA Women’s World Boxing Championships. “It’s not just because I say it. It’s because I’ve taken on the best challenges – wherever, whenever, against whoever. And I’ve beaten them. If they feel this is the girl who’s gonna knock me out and she’s gonna, you know, take all my belts and all this stuff, I wanna give the fans and the world a chance to witness this fight and to see that everything I’ve been saying is that I’m not cocky. I am confident and I believe 100 percent in my skills, my offense, my defense and in my power. And I believe that I’m a great boxer, and I am the greatest woman of all time, and that she doesn’t have what it takes to beat me.”

The 27-year-old Shields, of Flint, Michigan, has been down just once as a pro. Hanna Gabriels sent Shields to the canvas in the first round, but Shields got up, recovered quickly and beat Costa Rica’s Gabriels (21-2-1, 12 KOs) by unanimous decision in a middleweight title fight that took place in June 2018 in Detroit.

Only two of Marshall’s past eight fights have gone beyond the third round.

“First she was saying she was gonna knock me out in the second round,” Shields said of Marshall. “Then she started saying she was gonna hurt me and outbox me. But I was hurt by Hanna Gabriels up in the first round and I came back throughout that fight and won unanimously. So, the only way she’ll be able to get the victory over me is to use her [one-punch] knockout power, and she gotta land clean. And when she land clean, if I go down, she has to deal with me getting back up. And I’m gonna be mad as hell if I gotta get back up.”

Despite Shields’ accomplishments, most handicappers have installed Marshall as a slight favorite.

Sky Sports will televise Shields-Marshall as the main event of an all-women’s card in the United Kingdom and Ireland. ESPN+ will stream the entire event in the United States.

Keith Idec is a senior writer/columnist for He can be reached on Twitter @Idecboxing.