Alex Ritson

The match has been dubbed the Battle of the Sexes, but it's not the first time such an encounter has taken place.

In 1973, when one of the greatest players of all time, Billie Jean King, took on a former men's Wimbledon champion called Bobby Riggs.

King won the match.

In an interview with the BBC afterwards, she described it as one of the most important wins of her career.

Some of the rules have been changed to balance out the differences between the way men and women play the game.

But Irina Sabalenka and Nick Kyrgios have defended the encounter.

My colleague Joe Pike spoke with Charlie Eccleshare, tennis correspondent for The Athletic, who began by explaining some of those rule changes.

Firstly, each player will only get one serve.

So that's kind of designed to mitigate the fact that Kyrgios has a huge serve.

So the idea is that that makes it a bit fairer, a bit more competitive.

The other is that based on some science, apparently, and don't shoot the messenger here, male athletes cover ground about 9% quicker than women ones, or that may be men and women in general.

And so the court dimensions are slightly smaller.

And so Kyrgios will be hitting into a court that's 9% smaller.

than the one Sabalenko will be hitting into.

So they'll stay on the same side.

They'll still have kind of change of ends in inverted commas where they sit down every couple of games, but they won't actually be changing ends.

And how have the tennis world reacted to this since it was announced?

I'd say it's been...

divisive might be generous I mean as Nick Kyrgios said it certainly generated a lot of talk and chatter and I think a lot of people will watch it but I think there's a sense that it's kind of lose-lose for Sabalenka and therefore the kind of women's tennis movement and women's movement in general because you know talking about the women's world number one playing against a guy who's been injured for most of the last three years really ranked 671st and if Sabalenka wins then it's kind of like well okay you beat a guy who's

or she loses and it's, oh my gosh, the world number one loss to this guy who barely plays and is so lowly ranked.