From metal band bassist to two-division boxing champion: the story of Mikaela Mayer

Mikaela Mayer (L) with a left hook during the WBA, WBC and WBO super-welterweight unification bout with Mary Spencer on Oct. 30, 2025. Photo by AP

The 35-year-old American boxing star achieved the rare feat on Oct. 30 at the Casino de Montreal in Canada. Mayer defeated Mary Spencer by unanimous decision to unify the WBA, WBC and WBO super-welterweight titles, a feat that was previously achieved by boxing legend Cecilia Braekhus.

While Spencer started the match strong, Mayer quickly dominated, controlling the tempo and landing accurate counter-attacks. From the fourth round on, Spencer fell short while Mayer maintained relentless pressure through all 10 rounds to secure the victory by points.

Mayer is now a title holder in two weight classes at the same time, with her new super-welterweight belts in addition to the WBO welterweight title she won from Sandy Ryan and successfully defended in March 2025.

This victory marks a new high in a career defined by reinvention. After winning bronze at the world championship in 2012 and representing the U.S. at the 2016 Olympics at the amateur level, Mayer turned professional in 2017 with a first-round knockout win.

In 2020, Mayer defeated Ewa Brodnicka to win the WBO super-featherweight title, then beat Maiva Hamadouche to win the IBF title in 2021. A year later, the American boxer lost to Alycia Baumgardner in a historic four-title unification fight in London.

Following that loss, Mayer moved up two divisions to welterweight, beginning her current championship run.

After her win against Spencer, Mayer set her sights on another ambitious goal: moving back down to welterweight to unify all the titles against Lauren Price, the Welsh fighter who holds the WBA, WBC, IBF, IBO and The Ring.

"I think the most important thing is that I have options," Mayer told ESPN. "I cleared my head after a tough two years. I'd love to do both, go down to 147 to become undisputed and defend at 154. I think I'm a natural 147-pounder. ... I can do both."

 

 

From metal band bassist to two-division boxing champion: the story of Mikaela Mayer

Diễn biến chính trận Mikaela Mayer thắng Mary Spencer

Before she ever stepped into a ring, Mayer was a musician. As a teenager, she was the bassist for the all-female heavy metal band Lia-Fail, which featured Nita Strauss, now the lead guitarist for Alice Cooper. At 15, she already performed at Warped Tour, one of the biggest rock festivals in the U.S.

"Before boxing I was a little metalhead, my nose was pierced, my tongue was pierced, I had my ears pierced, hair was black, everything I wore was black, it was definitely a fun time," Mayer told BBC.

After leaving the band, she went to a gym at 17 and changed course into boxing.

"I was smoking a pack of cigarettes a day when I first walked into this gym and within a week, I was like, well, can't do this anymore. I want to be the best female fighter in the world," she added.

Since then, she has qualified for the 2016 Olympics and turned professional, where she became one of the greatest female boxers of her generation, alongside Katie Taylor, Amanda Serrano and Claressa Shields.