Natasha Jonas column: Claressa Shields v Savannah Marshall will redefine women's boxing

Boxing analyst and current WBO and WBC super-welterweight champion Natasha Jonas writes for BBC Sport about the undisputed clash between American Claressa Shields and Britain's Savannah Marshall on an all-female card at London's O2 Arena on Saturday.

IBF, WBA and WBC middleweight champion Shields has only lost once as an amateur and professional, against WBO holder Marshall in the World Championships in 2012.

Will the away fighter gain revenge? Or will Marshall extend her unbeaten professional record? And what does the historic bout mean for women's boxing?

An undisputed clash between two elite fighters, on a card featuring an all-female cast - it does not get much bigger, or better, than that.

When American Christie Martin fought on a Mike Tyson undercard in 1996, it was huge for women's boxing because nobody had ever had a platform like that before.

Then earlier this year, Katie Taylor and Amanda Serrano sold out New York's Madison Square Garden in a historic moment for the sport.

Now we have another game-changing event which will redefine women's boxing.

Saturday night will leave behind a legacy. It will set the tone for everything else which will follow in the years to come.

The whole card is the biggest thing to happen in British boxing for women. When you get a crest of wave like we have now, you have to ride it, and enjoy it.

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Marshall will land that one punch KO

The main event has been 10 years in the making. They are two totally different people. Savannah is quiet and introverted, whereas Claressa is hard, brash and outspoken - I've had my own back and forth with her in the past.

It has the feel of a Nigel Benn v Chris Eubank rivalry, and women's boxing needs that. We need different characters. The men have the pretty boy character, the flash boxer, the trash talker, whereas we haven't quite developed that in women's boxing yet but we're getting there.

Claressa has the opportunity to right the only wrong that has blemished her boxing record, while Savannah has the opportunity to set her straight.

This is a genuine 50/50 fight, which boxing fans are always screaming out for, and it's a rivalry which isn't forced or manufactured. They really don't like each other.

The general feeling is that Claressa will win on points or Savannah will be victorious by knockout, and I do buy into that.

Savannah can box, make no mistake. She is a great technical fighter. But if pushed for a prediction, I think Claressa will be winning on the cards when Savannah lands and wins by stoppage. She has that one-punch power which is just devastating.

In 20 minutes, with 10 two-minute rounds, a shot will definitely land. Claressa can be elusive for a while, but not for the whole fight.

People think she is invincible, however she was dropped in her sixth fight by Hanna Gabriels. She has the potential to be hurt.

Briton on cusp of pound-for-pound stardom

Savannah has got more confident under the tutelage of trainer Peter Fury. She has a bit of banter now. For years before, she didn't.

She could always speak with ease amongst people she knew but couldn't quite do it outside of her circle.

Now she has that confidence and is ready to announce herself. It's great to see that development.

I've known her since she was 15. As a kid we could see how good she was but she never really believed in herself. Now she does, and that makes her dangerous.

If Savannah wins, it puts her up there with the likes of Serrano and Taylor as a pound-for-pound star.

But a loss for either fighter does not mean the end of a career. Savannah in particularly would need to take some time to pick herself back up and rebuild.

Defeat will damage Shields' ego

Double Olympic gold medallist Shields is a multiple weight world champion as a pro

A loss would be damaging to Claressa's ego rather than her boxing reputation. She calls herself the 'Greatest Woman of All Time', and she 100% believes she is the GWOAT.

As a nation, us Brits don't really take to that. We like to be humble. We had it with Prince Naseem Hamed, I'd say more people went to see him lose than win. We didn't like it when Floyd Mayweather did it. And it's the same with Claressa.

When she lost to Savannah in the amateurs, it was a real shock to her. She came up against a more experienced fighter, someone a little older than her. But she went away and really worked on her game and has become a superior boxer.

However I worry about how the boxing world will react if she is defeated again, and how Claressa then reacts on social media.

A loss can be devastating when you have put yourself on that pedestal. A GWOAT is something everyone else should call you. If she loses, people will jump on her back.

But if she wins, then the GWOAT status is a conversation we can have. You have to start using her name in the same breath as the likes of Cecilia Braekhus, Laila Ali, Lucia Rijker or Ann Wolfe.

Mayer-Baumgardner could steal the show

There was talk of me fighting on the undercard, but instead I boxed to unify the super-welterweight division. Although it is disappointing not to fight on this historic night, I just could not let the opportunity of competing in front of my home fans pass me by.

The chief support - an all-American super-featherweight clash between Mikaela Mayer and Alycia Baumgardner - could steal the show on Saturday night.

I was around both women before the original fight date in September, and their bad blood is definitely genuine. They both have a real presence when they come into the room. Baumgardner has that one-punch KO power and Mayer has the ability to outbox her.

We have two international superstars fighting in Britain. It's worthy of being a top-of-the-bill fight. It once again shows how we are leading the way for female boxing. You even have boxers such as Australian duo Ebanie Bridges and Skye Nicolson relocating to here.

Also on the undercard, there's Caroline Dubois who is such an unreal talent, while Olympians Lauren Price and Karriss Artingstall are stars in the making who will continue their professional development.

All three are capable of becoming world champions; if they don't then somebody has failed them. For them to be involved in big nights like this is just invaluable. You can't buy that experience.

From wearing leftover kits to historic all-female card

We are at a pivotal moment in women's boxing, having already knocked down so many barriers. We always knew as athletes how good female boxing was, we just needed the world and the platform to see it. Now we have that.

When I first started, women's boxing wasn't even an Olympic sport. I'd be fighting for England and we didn't even have our kit, just the leftovers from the lads.

We had two England tops when we were competing. One was a small and one was an extra large. Only Savannah was big enough to wear that one.

You had to run, go give it a quick wash, then hand it to the next person. You had to pray you weren't fighting last that day as you'd be wearing everybody else's sweat.

Now look where we are at. Some may say an all-female card is not progressive, but for so many years it's been all-male.

You speak to British fighter Jane Couch and she will tell you that women's boxing was seen as a joke. She had to go to the United States, she wasn't even allowed to box here.

This weekend will show that all the ideologies some people have about women's boxing, saying it is not as good or hasn't got the depth, is inaccurate.

Then afterwards we move on and we can make the sport more inclusive. It won't be about male and female; finally we will be able to call it just 'boxing.'

Natasha Jonas was speaking to BBC Sport's Kal Sajad.