What began as a makeshift placeholder could wind up as a career changer for Mikaela Mayer.

For now, it’s just business as usual for the two-division and reigning WBO 147lbs titlist.

The stakes have raised since Mayer agreed to move up in weight to challenge reigning WBA 154lbs titlist Mary Spencer. Three belts (WBA, WBC, WBO) are now on the line in their scheduled 10-round affair on Thursday in Montreal, Canada. 

A win by Mayer, 21-2 (5 KOs), will not only mark her third divisional title reign but also place well within reach of her years-long career goal to become undisputed champion. Oshae Jones holds the IBF belt and has a wide-open schedule following her July 25 title-retaining split decision victory over Ella Carranza. 

For now, the always business-savvy Mayer is content to focus solely on the task at hand. 

“I have a big job to do on Thursday night,” Mayer noted during Tuesday’s final pre-fight press conference. “It’s always been my goal in this sport to go and search out the best fights possible; the biggest names possible.”

That search led to her securing a title shot against Montreal’s Spencer, 10-2 (6 KOs), a naturally bigger fighter who also enjoys hometown advantage for their three-belt affair.

“She’s a worthy opponent,” Mayer said of the current 154lbs titleholder. “She’s done a lot in the sport. You know, I remember her name from back in the day. She was the it girl back in the amateurs.

“Those are the type of names I want to add to my resume, and we got the fight done, so I’m happy to be here.”

Mayer entered 2025 determined to claim all of the remaining hardware at welterweight. 

She lifted the WBO 147lbs title in a narrow victory over England’s Sandy Ryan in September 2024 in New York City. Their rematch in March was considerably less competitive. 

In fact, it was a statement-making performance by Mayer, a former unified 130lbs titlist who immediately next set her sights on lineal, WBA, WBC and IBF 147lbs champ Lauren Price. 

The timing was perfect for such a clash. Price defeated Natasha Jonas – who edged Mayer via split decision in their thriller in January 2024 – in their three-belt unification bout in March, just three weeks before Mayer retained her WBO belt. 

Unfortunately, the business side of the sport torched their best-laid plans. 

Price is promoted by Boxxer, whose deal with Sky Sports ended earlier this year and who’s yet to successfully launch their new-found partnership with BBC Sport. Their first show was postponed to late November, though Wales’ Price – a 2020 Olympic gold medalist for Great Britain – has not seen her name attached to any fight dates in the immediate future. 

Meanwhile, Top Rank – Mayer’s career-long promoter – remains without a network deal. The company’s content aired exclusively in the US on ESPN and its platforms since 2017 – the entirety of Mayer’s pro career has aired either on ESPN or ESPN+. 

Their extended seven-year pact ended with Top Rank’s show in July in New York City, leaving its stable to hit the road. 

For the 35-year-old Mayer, it meant searching for any title not yet spoken for, which meant another move up in weight. She has the frame to compete and even run the tables at 154lbs, as well as the discipline to campaign at 140lbs if fights with two-division or unified champ Katie Taylor and/or WBC titlist Chantelle Cameron were to surface.

Ideally, a return to 147lbs to finish what she started is the best fit. However, Mayer, 35, is not one to allow her career to grow stale. Her desire to keep the line moving is what led to this new challenge.
“I’ve had a great career so far,” Mayer confidently stated. “I did my thing at 130. I moved up to 147 and became a champion there, but my goal is to go undisputed. I couldn’t get that undisputed fight against Lauren Price at 147, so my goal is to find the next best challenge for me. And when Mary Spencer’s name came up, I said, ‘Yep, let’s go to 154. Let’s take that challenge.

“There are lots of big fights ahead of me, but the number one goal right now is to put on a great performance, show everyone that even though I’m the smaller fighter, skills pay the bills. Size doesn’t win fights, skill does. So, that’s what I’m going to do Thursday night.”

Spencer-Mayer will stream live on its Top Rank Classics FAST channel via ROKU, Tubi, VIZIO and Pluto TV, beginning at 8:00 p.m. ET/5:00 p.m. PT.

Jake Donovan is an award-winning journalist who served as a senior writer for BoxingScene from 2007-2024, and news editor for the final nine years of his first tour. He was also the lead writer for The Ring before his decision to return home. Follow Jake on X and Instagram.