Taylor, 38, is an Olympic gold medalist and undisputed champion at both weights. Puerto Rican Serrano has won world titles in an astonishing seven divisions.

They earned more than £1 million each for the first fight – the first women’s contest to headline New York’s Madison Square Garden – and will again, deservedly, be rewarded with seven figures.

“It’s every fighter’s dream to have big salaries and I love my sport, I love what I do,” Taylor says, downplaying reports that it could reach $6.1 million ( £4.8 million).

Serrano, 36, is also reluctant to reveal her purse, but believes other female fighters can capitalize on the scale and success of her rivalry with Taylor.

“Women’s boxing is getting better and it’s only going to get better from here,” Serrano says. “I just hope their salaries improve, just like mine and Katie’s.”

Despite their optimism, there are only a handful of female fighters whose competitions generate life-changing money, and their earnings are not reflected on a global scale.

Energy-rich Saudi Arabia is slowly building its boxing stronghold and paying fighters – some with lower profiles than Taylor or Serrano – handsomely.

However, even though Saudi Arabia’s first world title fight took place in October, women’s boxing has generally been neglected by the Kingdom.