Mayer vs Spencer Predictions: Mikaela aims high with three belts on the line

WBO welterweight champion Mikaela Mayer moves up to challenge WBA super welterweight champion Mary Spencer this Thursday, October 30. The fight takes place at the Montreal Casino in Quebec. Along with Spencer’s WBA belt, the vacant WBC and WBO 154lbs titles will be on the line. Stateside fans can watch through the Top Rank Classics streaming channel. No news at press time over a UK broadcast.

Read on for my Mayer vs Spencer predictions as Mikaela moves up.

Mayer vs Spencer Odds

Mayer is priced at 1/10 to get the job done on Thursday. Spencer is 5/1 to score the upset while the draw is priced at 16/1.

Mayer vs Spencer Fight Preview

This fight was a little surprising when it was announced. With Mayer wearing the WBO welterweight title and Welsh wonder Lauren Price holding the other three major titles at 147, both women were receptive to an undisputed championship showdown. Would Mayer moving up to super welterweight put a bullet in a big fight for women’s boxing?

Thankfully, the four-belt showdown with Price still seems likely and Mayer has been vocal in the build-up to this bout about wanting the Brit next. But as we have seen so many times in boxing, you cannot afford to look too far ahead. Mayer is locked-in on Spencer and she should be.

As side missions go, it is a prestigious one. Three of the four 154-pound straps are on the line, with only Oshae Jones’ IBF strap absent. Both Mayer and Jones are both Olympic medalists, meaning Mikaela could have her pick of marketable undisputed options if she beats Spencer.

Doing so is no foregone conclusion. Spencer was a legendary amateur, with three golds and a bronze across four World Championships before suffering an upset in the quarter finals of the London 2012 Olympics. 

Spencer turned pro at the age of 36, after having a break from competitive boxing following her Olympic disappointment. Only two-weight world champion Femke Hermans has beaten her in the pros, doing so twice in Spencer’s 12 fights. ‘Amazing’ Mary snagged the WBA interim super-welter crown against Naomi Mannes in September 2024. 

Spencer’s title was swiftly upgraded to the full shebang when Terri Harper vacated to move back down in weight. Spencer retained her world crown in April with a unanimous decision win over Ogleidis Suarez.

Mayer is an old-hand at annexing professional titles. She started with the IBF, WBO and The Ring titles at super featherweight. Mayer moved up to lightweight after losing those titles in a unification against WBC queen Alycia Baumgardner. The Spice Girls-loving stylist held the WBC interim title in her brief stop at 135lbs.

Super lightweight was another division where Mayer had a single fight as she found her ideal new home. A points decision over Silvia Bortot was the LA-born boxer’s only 140lbs outing before she moved to welterweight.

Mayer was given a rough landing at her new weight, with Liverpool legend Natasha Jonas out-scoring her in an IBF welterweight title fight. But the Californian has stuck at it. 

A controversial 2024 fight with Sandy Ryan was marred by allegations that one of Mayer’s team threw paint over the Brit before their 2024 meeting. But whoever threw the Dulux, Mayer won the fight via unanimous decision.

There was enough doubt over the outcome, and how much it owed to Ryan getting coated in emulsion beforehand, that a rematch took place. Mayer won that too in more dominant fashion. ‘MM’ had arrived at welterweight.

How far can Mayer go? So far, so good when it comes to leaps in weight. Only Jonas has beaten her since the American left her old super featherweight stomping ground behind. Every fighter has their limits, but Mayer is yet to find them. Can Spencer find them for her?

Mayer vs Spencer Full Card

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Mayer vs Spencer Prediction

Spencer is seasoned but, at 40, no longer the phenom she was in the amateur game. While she will always be one of the all-time greats in that arena, Mayer has run rings around her as a pro.

Will she do the same in the ring? I imagine so. Maybe not run rings, but I think Mayer outpoints Spencer comfortably. She is 1/10 to win on the night.

You can find all our latest boxing betting tips and analysis at our Betfred Insights Boxing page and our latest boxing odds here.

Image: Vitor Munhoz/Eye Of The Tiger via Top Rank Boxing