Their history and the possibility that they might fight one day will encourage Shields to root for Mayer to beat Brit Chantelle Cameron in their 154-pound championship unification clash August 29 at bp pulse LIVE in Birmingham, England.

In Shields’ expert opinion, though, their 10-rounder will unfold as one of the most difficult fights of Mayer’s career.

“Chantelle Cameron versus Mikaela Mayer is a really good fight,” Shields told The Ring. “I think Mikaela has more skill than her in some ways, but I think that a lotta people really don’t know Chantelle Cameron is really a big girl. I can’t wait to see how Mikaela can deal with her punch and deal with her aggression. But I’ve seen Mikaela has been working really hard, so I actually see that as a 50-50 fight between those two.”

Most sportsbooks have made Mayer (22-2, 5 KOs) almost a 3-1 favorite over Cameron, whose lone loss is a majority-decision loss to Irish legend Katie Taylor in their rematch in November 2023. Cameron (22-1, 8 KOs), a former undisputed junior welterweight champ who won their first fight by majority decision, is the only opponent to beat Taylor (25-1, 6 KOs) in the professional ranks.

Mayer, a Las Vegas resident raised in Woodland Hills, California, has dropped only a pair of split decisions to Alycia Baumgardner (18-1, 7 KOs, 1 NC) and Natasha Jonas (16-3-1, 9 KOs) in junior lightweight and welterweight title fights, respectively. The former IBF/WBO junior 130-pound champ has climbed to the No. 3 spot on The Ring’s pound-for-pound list since her loss to Jonas by beating former WBO welterweight champ Sandy Ryan (9-3-1, 3 KOs) in back-to-back bouts and out-pointing Mary Spencer (10-4, 6 KOs) in a junior middleweight championship match.

England’s Cameron, 35, and Mayer, 36, will fight for Cameron’s WBO and Mayer’s WBA and WBC 154-pound titles. ESPN+ will stream Mayer-Cameron in the United States and Sky Sports will televise it in the United Kingdom.

Mayer’s improvement has impressed Shields (18-0, 3 KOs), who dropped back down to the middleweight division to face WBA/WBC champ Kaye Scott (5-1-1) on Saturday night at State Farm Arena in Atlanta (DAZN; 9 p.m. ET; 2 a.m. BST).

“I always go with the home team, so of course I would ride with Mikaela to win,” Shields said. “But I know Chantelle Cameron is not a pushover. She has a win over Katie Taylor, and that’s very hard to do. And I think the weight class they’re fighting at, I feel like that favors Chantelle Cameron. She doesn’t have to lose so much weight, keeps some of her strength, and she has a big punch. So, I’m looking forward to seeing it. I think it’s 50-50.”

Shields is a 20-1 favorite to beat Australia’s Scott, according to DraftKings. Assuming Shields emerges victorious, she hopes a middleweight title fight against Ring, IBF, WBA and WBC welterweight champ Lauren Price (10-0, 2 KOs) is next.

If not, the five-division champ from Flint, Michigan, would welcome a bout with Mayer. The Cameron-Mayer loser would be expected to exercise her contractual right to an immediate rematch, however, which could complicate Shields’ search for her next opponent if Price’s handlers don’t finalize the deal they’ve been negotiating with Dmitriy Salita, Shields’ promoter.

Shields is ranked No. 2 on The Ring’s pound-for-pound list. Cameron is No. 5, and Price is No. 8.

“I’m not waiting around for nobody,” Shields said. “After this fight with Kaye Scott, I would love to be back in the ring by December or January. So, if Lauren isn’t ready by then, maybe I can take Mikaela up on her word, because she said she would come to 160, and she can fight me for some belts.”