Claressa Shields on fighting in the UK and Savannah Marshall possibility

Claressa Shields made her professional boxing debut in 2016 and has won all 11 bouts, with two stoppages

Two Olympic gold medals, a three-weight world champion and the first boxer - male or female - to be undisputed champion in two divisions in the four-belt era - Claressa Shields is already one of the most decorated fighters in boxing history.

But the 26-year-old American does not take too kindly to the words 'self-proclaimed' being prefixed to her 'Greatest Woman of All Time' alias.

"When people say 'self-proclaimed' that's narcissistic, which I'm not," she tells BBC Sport.

"My accomplishments, performances, skills and history-making - that's why I'm the GWOAT. Fact."

Shields will fight in the United Kingdom for the first time as a professional when she defends her WBA, WBC, IBF and Ring magazine middleweight titles against Slovenia's Ema Kozin at Cardiff's Motorpoint Arena on Saturday night.

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'UK fans prefer Joshua's attitude to Fury's attitude'

Shields is expecting a mixed reception in Wales, suggesting some British fight fans will appreciate her skills while others may mistake her confidence as arrogance.

"You guys like the Anthony Joshua attitude more than you like the Tyson Fury attitude," the Michigan fighter says.

"There's nothing wrong with that but fans need to understand when there's a fighter who is in the gym and putting in the hard work, then there is nothing wrong with us to have confidence and praise ourselves for our wins.

"We have to beat ourselves up when we lose so why not uplift ourselves we win."

Shields has added trainer Gerald Tucker to her team, joining long-time coach John David Jackson, and has also been receiving tips and guidance from former pound-for-pound star Floyd Mayweather.

"My preparations have been crazy," she says. "I went to Vegas for altitude [training] for this fight, spent some time with Floyd and added coach Tucker - who works the corner for Floyd when he has exhibition fights - to my team".

Mandatory challenger Kozin is undefeated in 22 fights, but Shields can only see one outcome.

"She's going to try and push the pace and show me she's not scared of my reputation," Shields says. "But if she does that, she'll get hurt. If she tries to outbox me, she'll get hurt."

'Marshall is a hater'

WBO champion Marshall (left) has won all 11 professional bouts and will face Belgian mandatory challenger Femke Hermans in Newcastle on 12 March

A win on Saturday sets up a blockbuster undisputed clash between Shields and WBO champion Savannah Marshall, provided the Briton comes through a mandatory defence in March.

There is no love lost between the two. In 77 fights as an amateur, Shield's only loss was against Marshall in the World Amateur Boxing Championships in 2012.

A rematch has been in the making ever since both fighters turned professional, and the verbal exchanges and rivalry intensified further when Marshall won the world title vacated by Shields in October 2020.

"I've seen Savannah in person a couple of times and there's always been mutual respect but then she started being disrespectful last year," Shield says.

"She's just a hater. She can't accomplish anything I have; in the pros or amateurs.

"I have 12 world titles and she has one and she's still yelling and barking my name. She's celebrating a win when I was 17. Get over it and move on. Show some respect."

The rivalry could finally be settled in the ring this summer, with Boxxer promoter Ben Shalom suggesting Shields-Marshall may take place in Newcastle in June.

With Marshall expected to be in attendance in Cardiff this week, Shields has warned her fellow champion she will not shy away from any confrontation should the two come face-to-face.

"After I beat Ema Kozin I know they want Savannah to come inside the ring," she says. "For the past year she hasn't given me respect and said a lot of bad things and I'm not a person who will shrug that off when I see you in person and give you hugs and kisses. "

'Taylor v Serrano is bigger than Shields-Marshall'

Ireland's undisputed lightweight champion Katie Taylor will defend her titles against American Amanda Serrano in New York on 30 April in what will be the first female fight to headline Madison Square Garden.

Shields says Taylor-Serrano is "huge" for the sport and "much bigger" than a potential showdown between her and Marshall.

"I'm not a hater and people make it seem like I throw shots at other fighters," she adds.

"You have Serrano, a seven-time world champion, and Taylor, an Olympic gold medallist, two-division world champion and undisputed champion.

"And then you have the GWOAT Claressa Shields, 12-time world champion, three division world champion, two time undisputed, versus WBO champion Marshall.

"Savannah is one-time world champion. Does she have any Olympic gold medals? Nope. That's why their fight is bigger."

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