As the first two-time Olympic gold medalist in United States amateur boxing history, Claressa Shields has never been one to pull any punches when talking about her own greatness inside the ring.
Shields (8-0, 2 KOs), the unified middleweight champion, began openly referring to herself as the best pound-for-pound fighter in the sport not long after turning pro in 2016. After employing a dare-to-be-great matchmaking strategy which included winning her first world title in her fourth pro fight and unifying titles in a second weight class just one year later, the 24-year-old Shields soon began calling herself the greatest female fighter of all time.
So it's hard to consider it hyperbole when the brash native of Flint, Michigan, calls Saturday's middleweight unification bout against Christina Hammer (24-0, 11 KOs) at Boardwalk Hall in Atlantic City, New Jersey (Showtime, 9:10 p.m. ET), the biggest women's fight in history.
"I think it's the biggest women's boxing match to date because you know who both of us are," Shields told CBS Sports' State of Combat last week. "Just the flame that women's boxing has with me being in the Olympics twice, me winning world titles and becoming the first woman to main event on Showtime on premium cable and me fighting on HBO and DAZN co-main events, it just shows how much women's boxing has grown.
"It's not a disrespect to any other fights that Laila Ali had or Christy Martin, Lucia Rijker or Ann Wolfe, but when they fought, you really didn't know who their opponents were. I think with this fight you have two women who are greatly known and then you have a champion who has been reigning from eight years across the way and we are fighting each other for all of the belts."
Listen to our interview with Claressa Shields on the State of Combat with Brian Campbell podcast as she previews her title fight this weekend, and be sure to subscribe in the embed below.
In Shields' favor are the historic elements associated with this fight. Not only will an undisputed middleweight champion be crowned for the first time but the winner will join current welterweight champion Cecilia Braekhus as just the second women's undisputed champion -- and sixth overall alongside Bernard Hopkins, Jermain Taylor, Terence Crawford and Oleksandr Usyk -- in the four-belt era. The fight has also received tremendous promotion from Showtime which included a two-part "All Access" documentary series following around both fighters during training camp.
The rivalry between the two fighters first gained steam in 2017 following Shields' title win over Nikki Adler when Hammer entered the ring to exchange words and hype a future fight between the two. Then, a second and much more heated exchange complete with shoving took place after Shields got up from the deck to outpoint Hanna Gabriels last June which only fueled the beef between them even more.
At last month's press conference to announce the bout, the 28-year-old Hammer said she has nothing personal against Shields and that the talk between them was strictly professional. It's a claim from that Shields believes just isn't true.
"She's lying. She's talking about how she doesn't have anything against me personally. Big, fat liar. Period. She's lying," Shields said. "She had something against me because she knows I boxed better than her and got more recognition than her and she doesn't like that, along with a couple of other women who thought they should have been getting the recognition Claressa's getting but they haven't accomplished nowhere near what I've accomplished just in my 24 years of life.
"[Hammer] carries that with her and she's upset now that I'm the favorite to win even though she has been the reigning champion for eight years. Of course she doesn't like me, but she can say whatever she wants to say to the media, but I already know for a fact she doesn't like me. That's why she said we could never be friends. Well, I don't want to be your God damn friend anyway. I don't care."
Shields vs. Hammer odds
|Claressa Shields (c) -300|
Christina Hammer (c) +240
Undisputed women's middleweight title
A native of Kazakhstan, Hammer has fought all but six of her 24 pro bouts in her new home of Germany and remains successful outside of the ring as a fashion model. The two fighters exchanged heated words once more at the press conference when Hammer accused Shields of being jealous that she isn't as pretty.
"That's her life. She cares about how her body looks and how her face looks to people. She likes that kind of attention," Shields said. "I don't care about that. I'm all about the sport. The sweet science, the muscles, the hard hitting -- that's what I'm all about. I don't get mad when it goes into that because, I'm going to be honest, I don't think 'The Hammer' is that good looking of a girl.
"I don't get mad when she talks about me being jealous of her face. I love my face, I love my teeth, I love my body shape. She just doesn't have anything to say."
The fight was originally scheduled for last fall until Hammer pulled out with an undisclosed illness. It was a result that Shields had predicted while texting her co-manager Mark Taffet during the introductory teleconference to announce the fight when Shields thought Hammer's answers lacked any form of life or excitement.
In the time between the fight was rescheduled, Shields kept busy with decision wins over Hannah Rankin and Femke Hermans over a 21-day period. Hammer, who won her first world title at age 20 in 2010, came back in February to stop Elene Sikmashvili in a stay-busy fight.
"She keeps talking about her jab and her movement, but she isn't saying how she is going to beat me," Shields said. "She is so scared to acknowledge in her mind that I'm stronger than her, that I'm faster than her, that I can keep up with her. She doesn't want to acknowledge that in her mind.
"My one goal is to always win but if I can knock her out, trust and believe me I will do it. I do have the ability to do it. I believe that I can put Christina Hammer out. Yes."
The fight is a classic style matchup between the boxer Hammer, who has a slick jab and advantages of three inches in both height and reach, against the aggressive punching Shields who does her best work inside. How well Shields can dictate the pace and distance of the fight, including whether she can begin to wear down Hammer early by crowding her and going to the body, should dictate whether she can get ahead on the scorecards early.
Although neither fighter is considered a one-punch threat from the standpoint of knockouts, Hammer has stopped 44 percent of opponents as opposed to just 25 for Shields. Yet Shields has talked openly about Hammer's preference to stay in Germany and not seek unifications, meaning she doesn't believe Hammer has ever faced a fighter as quick or as skilled as her.
If Shields can throw and land more punches and is able to lure Hammer into a pace she's not comfortable with, thus succeeding in making it more of a fight than a technical showcase, look for the American star who has been the face of women's boxing since before she even turned pro to come out on top. Pick: Shields via UD10
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