Everything you need to know as Sandy Ryan defends her WBO welterweight world title against former world champion Mikaela Mayer in a highly-anticipated meeting at Madison Square Garden in New York on Friday night.
Beyond prizes, purses and pride there is an enmity that runs deep between these two elite-level competitors, who have everything to gain and even more to lose.
Ryan is making the third defence of her world title, while top American Mayer is coming off a defeat on her welterweight debut, derailing her campaign to reclaim a belt.
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Mayer, a 2016 US Olympian, jumped out to a 17-0 record to begin her pro career while winning a pair of super-featherweight world titles.
The Los Angeles native returns to America after a four-fight run in England that included a contentious 2022 split decision loss to Alycia Baumgardner in a bid for the undisputed super-featherweight title.
Mayer won a pair of decisions in 2023 as she moved up in weight to prepare for a welterweight world title opportunity. In January, she lost a debated split decision to IBF champion Natasha Jonas.
While a Jonas rematch did not materialise, Mayer now has another chance to become a two-weight world champion.
Ryan, from Derby, turned pro in 2021 after an accomplished amateur career that included a 2018 Commonwealth Games gold medal and a 2014 World Championships silver medal.
Her lone defeat - a March 2022 split decision to Erica Farias - was avenged less than five months later with a unanimous decision triumph.
Ryan picked up the vacant WBO title in April 2023 with a unanimous decision over Marie-Pier Houle.
Following a highly contentious draw with Jessica McCaskill in a title unification tilt, Ryan notched her signature victory in March with a devastating fourth-round knockout over former two-division world champion Terri Harper.
"It's the perfect moment in my career, and I'm looking forward to successfully defending my world title. I can promise that on a level playing field, nobody is taking this belt from me," said the 31-year-old.
"Mayer has had an awful lot to say about me and this fight, and I'm sure she will continue to do so, but I'm an athlete and a professional. I will let my boxing do my talking, and I will shine in that ring.
"Bring it on!"
Why the bad blood?
The enmity between the main event fighters was stoked further when Ryan began working with the American's training team, prompting Mayer to leave the gym.
Kay Koroma, who helped train Mayer from Olympic standout to professional world champion, is helping train Ryan for this career-defining main event.
Mayer said: "I need a team who is fully Team Mikaela. I need to trust whoever's in my corner. I can't have someone in my corner buddy-buddy with my opponent. There's a lot on the line for this fight and I need every box checked, I need to be 100 per cent mentally and physically."
When can you watch the fight?
Ryan defends her world title against Mayer at the iconic Madison Square Garden in New York. You'll have to set your alarms early on Saturday morning. The action starts live on Sky Sports Main Event and Sky Sports+ from 2am.
DuBoef wants Mayer to become a world champion again!
"Mayer is fighting above the weight that she's excelled at and was a champion, so I think this is going to be a big test and Ryan is a good puncher but I want the fight for Mayer," Top Rank president Todd DuBoef told Sky Sports.
"I think it's a 50/50 fight - really tough fight. I think Mikaela is probably the better boxer but when people start going up in weight things change drastically, but this one I want for her."
Jonas awaiting winner?
IBF champion Natasha Jones wants to fight Mayer a second time to leave no doubt that she deserved the decision in their first fight.
"That's what I believed I could do. I beat her the first time, I'd beat her more convincingly the second," she told Sky Sports.
What's happening on the undercard?
Two of boxing's most promising emerging talents, Puerto Rican super-welterweight Xander Zayas and Brooklyn-born featherweight Bruce "Shu Shu" Carrington, will see action in separate 10-round contests.
Zayas will face Mexican contender Damian Sosa, while Carrington looks to turn away the upset-minded Sulaiman Segawa.
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