This past Saturday night at the O2 Arena in London, Claressa Shields avenged her only defeat in a boxing ring - when she outboxed and outfought Savannah Marshall over ten rounds to secure a unanimous decision.

For the second time in her career, she became the undisputed world champion in the middleweight division by adding Marshall's WBO world title to her WBA, WBC, IBF straps.

Marshall decisioned Shields back in 2012 - when the two were amateurs. It became the only defeat for Shields in a boxing ring.

The amateur outcome fueled a rivalry that spanned 10 years.

Shields became an undisputed world champion for a third time in her career.

Former cruiserweight champion and Sky Sports pundit, Johnny Nelson, was very impressed with Shields' performance.

"I though she [Shields] was outstanding. She backed up every boast," said Nelson to Sky Sports.

"She was one step ahead in every department when it came to Savannah. Like it or not, she did everything you expected of her, she was sharp, she was fast, she was hungry, she was lean and she fought with intention. She made it a show, even the entrance, showing up in a glittery ball gown in a Bentley that probably went 200 yards but then she made sure she made a show of it. Then the entrance, the performance and then the speech afterwards.

"I actually think she has made herself a hell of a lot more fans over here in the UK and listen there were die hard Savannah Marshall fans but even Savannah said, the best woman won tonight and that is how it was. It is her business and these days it is not about just being a good fighter it is about having that whole package. You have got to have attitude, character and you have got to give them entertainment.

"I remember Prince Naseem Hamed when people used to come and see him fight, they used to go and just watch the entrance and I think Clarissa thought 'I am going to make a business of this'. She had the dancers out there, good fight, lots of energy, nice and upbeat and she doesn't mind being the villain or the hero but either way she backed up the boast."