Multi-division world champion Mikaela Mayer is chasing history once again. The American standout will attempt to capture a world title in a third weight class, when she challenges Canadian star Mary Spencer for the WBA super welterweight world championship Thursday, October 30, at the Montreal Casino in Montreal, Canada. The stakes have grown even higher, as the vacant WBC and WBO titles will also be on the line, making this a rare three-belt showdown at 154 pounds.

Mayer (21-2, 5 KOs) enters the bout fresh off a dominant run at welterweight. After edging England's Sandy Ryan via majority decision in September 2024, she solidified her hold on the division with a decisive victory in their March rematch. Now, the 2016 U.S. Olympian and former unified junior lightweight champion Mayer steps up once more, seeking to cement her legacy among boxing’s elite multi-division champions.

Across the ring stands Mary Spencer (10-2, 6 KOs), a 2012 Olympian and one of Canada’s premier female fighters. Spencer successfully defended her WBA crown in April with a unanimous decision over former world champion Ogleidis Suarez. Fighting on home soil and backed by a passionate Montreal crowd, Spencer sees Thursday night as an opportunity to prove the odds makers wrong.

“I saw the odds. I know I’m the underdog according to the bookies, but they get it wrong often,” Spencer said at Tuesday’s final press conference. “I don’t feel like an underdog. I feel like this fight is a gift. I get to be here at home, show my best to a hometown crowd, and I’m very excited for that.”

For Mayer, the bout represents both a new challenge and a homecoming of sorts. “I’m really happy to be back here in Canada,” she said. “I haven’t fought here since my amateur days, back when I first learned of Mary Spencer. It’s great to be back.”

The 34-year-old American emphasized her hunger to face the best. “It’s always been my goal to go and search out the biggest names possible,” Mayer said. “I did my thing at 130, became a champion at 147, but my goal is to go undisputed. When Mary Spencer’s name came up, I said, yep, let’s go to 154 and take that challenge.”

The event, promoted by "Eye of the Tiger Promotions" and Top Rank Boxing, will stream live on "Top Rank Classics" in the U.S. starting at 8 p.m. ET/5 p.m. PT. Fans can watch for free on major FAST streaming hubs or online at trboxing.co/TopRankClassics.

With three world titles at stake and two proud Olympians sharing the ring, Thursday’s main event promises to deliver high drama, world-class skill, and the potential coronation of boxing’s newest three-division queen.