America's best women's boxer Claressa Shields has joined forces with Floyd Mayweather

• Claressa Shields and Floyd Mayweather have joined forces.
• The American boxer is one of the premier fighters in the women's game.

America's best women's boxer Claressa Shields has joined forces with the former five-weight boxing champion Floyd Mayweather.

As a two-time Olympic gold medalist and a three-weight world champion, 26-year-old Shields is one of the most decorated fighters in combat sports.

Undefeated in 11 boxing matches, Shields has already scalped big-name opponents like Christina Hammer and Marie Eve Dicaire.

And on the eve of her February 5 fight against Ema Kozin at the Motorpoint Arena in Cardiff, Wales, Shields announced a partnership with Mayweather in which she is likely to prosper even further.

"One of my idols has welcomed me with open arms, thank you for the support and encouragement this camp," Shields said of Mayweather in an Instagram post this week. "It means the world to me."

Mayweather, 44, can be seen giving Shields advice on the heavy bag during a recent practise session posted to Twitter by the fast-rising boxer.

In an interview with Boxing Scene, she said: "Training with Floyd Mayweather has pushed my confidence even higher. He's very fond of my skills and my power."

Shields continued: "If I had to use one word for this camp, it would be: uncomfortable. I made sure that I got out of my comfort zone for this fight.

"I'm making sure that I have all my tools and going to the Mayweather Boxing Club has really sharpened those tools."

Shields added that Mayweather said he'd fly to the UK to watch her box Kozin in her fight next month.

Victory in front of a British audience could help negotiations for a super-fight against 30-year-old British boxer Savannah Marshall, who, like Shields, is undefeated in 11 matches and a world champion in her own right.

Shields, though, is not looking past Kozin. "I'm focusing on the person who has earned the right to fight me," she said.

"I've never overlooked an opponent and I won't just because of the Savannah Marshall fight."