Mikaela Mayer Outshines Mary Spencer to Claim Vacant Interim WBO Super Featherweight Title in Montreal Showdown

The Montreal Casino in Montreal, Canada, buzzed with intensity on October 30, 2025, as Mikaela Mayer captured the vacant interim WBO super featherweight title with a unanimous decision (98-92, 97-93, 96-94) over Mary Spencer in a 10-round war. Headlining a thrilling card featuring Canadian prospects, Mayer’s precision and ring IQ outmatched Spencer’s aggressive power, marking a triumphant rebound for the American. Broadcast details are pending, but the bout, starting at 9:00 p.m. ET, electrified a sold-out crowd of 6,500, fueled by Montreal’s fight-week energy, including fan meet-and-greets and a downtown boxing expo. X posts like @BoxingCanadaX called it “Mayer’s redemption clinic,” solidifying her as a 130-pound force.

Fight Overview

Mayer vs. Spencer topped the main card at the Montreal Casino, kicking off at 9:00 p.m. ET after prelims at 6:30 p.m. ET. Slated for around 10:15 p.m. ET, the fight carried high stakes: Mayer, 35, aimed to reclaim title glory after a 2024 loss, while Spencer, 40, sought to upset the odds in her home country. BetMGM odds favored Mayer at -250, banking on her technical edge, with Spencer at +200, buoyed by her knockout threat. X framed it as a skill-versus-power clash, with @WomenBoxingX posting, “Mayer’s finesse vs. Spencer’s bombs—Montreal’s in for a treat!” The 6,500 fans, hyped by fight-week events like a Bell Centre open workout and live music at Place des Arts, created a charged atmosphere. X polls leaned 60% toward Mayer’s experience, with 40% backing Spencer’s power, per @FightPulseX.

Mikaela Mayer The 35-year-old from Los Angeles, California, entered with a 20-2 record (10-1 major titles), including 5 knockouts. At 5’9” with a 66-inch reach, the orthodox fighter’s technical prowess shines, averaging 6.2 significant punches per round with 56% accuracy (Compubox). Her 2023 decision win over Lucy Wildheart showcased her adaptability. Training at Top Rank Gym with Al Mitchell, X clips showed her drilling counters to neutralize Spencer’s rushes. Her 70% jab accuracy and star appeal make her a draw, with @BoxingUSA tweeting, “Mayer’s back to dominate; pure class at 130.”

Mary Spencer The 40-year-old from Windsor, Canada, carried a 9-2 record (4-1 major titles), with 6 knockouts. At 5’11” with a 68-inch reach, the orthodox brawler’s power is fearsome, landing 5.5 power punches per round at 49% accuracy (Compubox). Her 2024 TKO of Cynthia Lozano earned this shot, highlighting her aggression. Training at Grant’s MMA & Boxing, X footage showed her sharpening hooks with Buddy McGirt. @CanadaFightX noted, “Spencer’s +200 odds are juicy for that KO power.”

The Fight: Round-by-Round Breakdown

Round 1: The Montreal crowd roars as Mayer opens with a crisp jab, using her footwork to circle Spencer. Spencer lunges at 1:20, landing a heavy right to Mayer’s body, but Mayer counters with a straight left at 2:30, causing a slight welt on Spencer’s cheek. Compubox tallies Mayer landing 20 of 38 punches to Spencer’s 10 of 25, with brief clinches. @BoxingTalkCA scores it 10-9 Mayer, tweeting, “Mikaela’s too slick; Spencer needs to close distance.”

Round 2-3: Spencer presses in Round 2, landing a looping hook at 0:50 that tests Mayer’s chin. Mayer responds with a three-punch combo at 2:00, targeting Spencer’s body. Round 3 sees Mayer’s rhythm take hold: she lands 28 of 45 punches, dodging Spencer’s wild swings. A cut opens above Spencer’s right eye at 2:45. Judges likely give Mayer both, 20-18, per @RingCanadaX: “Mayer’s picking Spencer apart; that jab’s money.”

Round 4-6: Mid-fight intensifies as Spencer traps Mayer on the ropes at 1:15 of Round 4, landing a body shot that draws a gasp. Mayer slips out, firing a counter uppercut at 2:20 that snaps Spencer’s head back. Rounds 5-6 are Mayer’s domain: she outlands Spencer 65-48, using angles and a stinging left hook. A Round 6 combination rocks Spencer briefly. Compubox scores both 10-9 for Mayer. @FightVibeX: “Mikaela’s in her zone; Spencer’s fading.”

Round 7-8: Spencer rallies in Round 7, landing a right cross at 1:30 that staggers Mayer, igniting the crowd. She outlands Mayer 18-15 in the round. Round 8 sees Mayer regain control, landing 25 of 40 punches, including a jab that deepens Spencer’s cut. Scores likely 10-9 Spencer in 7, 10-9 Mayer in 8. @BoxingBuzzX: “Spencer’s got heart, but Mayer’s IQ is unreal.”

Round 9-10: Final rounds deliver drama. Mayer dominates Round 9 with 30 of 50 punches, targeting Spencer’s body to slow her. Spencer swings desperately in Round 10, landing a hook at 1:45, but Mayer’s counters (22 of 35) and footwork seal it. Compubox finale: Mayer 185 of 330 to Spencer’s 125 of 280. Unanimous decision for Mayer, with @BoxRecGlobal confirming, “Mayer’s back on top—what a performance!”

Key Moments and Impact

Mayer’s Precision: Her 185 of 330 punches (56% accuracy) outclassed Spencer’s 125 of 280 (45%), with the jab (70% accuracy) dictating pace. @USABoxingX tweeted, “Mikaela’s a surgeon; that footwork’s elite.” Spencer’s Power: Her Round 7 stagger and 38 body shots kept her in it, but 49% accuracy couldn’t overcome Mayer’s volume. @FightCAX: “Spencer’s power was real, just not enough.” Fan and Media Reaction: The 6,500 fans roared for Spencer’s rally, but X polls favored Mayer 63%. @WomenFightX praised, “Mayer’s a queen,” while @CanadaBoxX noted, “Spencer fought like a lion.” Cut Impact: Spencer’s eye cut from Round 3 bled heavily, but her 5.5 punches absorbed per round showed grit. @RingPulseX: “Mary took a beating, never broke.”

Post-Fight Analysis and Implications

In the ring with ESPN, Mayer declared, “I’m back! Alycia Baumgardner, let’s unify!” Her 21st win, earning a $50,000 Performance of the Night bonus, marks a career resurgence. Her 6.2 punches-per-round average, 56% accuracy, and zero knockdowns absorbed highlight her dominance. A unification with Baumgardner looms, though her power against elite punchers is untested, per @BoxingInsiderX: “Mayer’s a star, but Alycia’s a test.” Spencer, now 9-3, hugged Mayer, saying, “She’s the best; I’ll keep climbing.” Her first title loss doesn’t dim her stock, with 5.5 power punches per round keeping her relevant. X suggests a rematch or a bout with Natasha Jonas, @BoxingGlobalX tweeting, “Spencer’s a warrior, back in ‘26.” At 40, her 49% accuracy ensures contender status. The super featherweight division heats up, with Baumgardner, Beatriz Ferreira, and Delfine Persoon circling. Mayer’s win sets up a title run, while Spencer remains a threat. The card’s 70% decision rate added technical depth.

Event Context and Montreal Atmosphere

The October 30 card was a Montreal fight-night gem, with the city’s boxing passion amplifying the action. The co-main saw Steven Butler TKO Kim Clavel in a super welterweight bout, while undercard prospect Leila Beaudoin scored a featherweight decision. The 6,500 fans, fueled by Montreal’s fight-week expo and open workouts at Olympic Stadium, created a fevered vibe. @BoxingMTL tweeted, “Montreal brought the heat!” The event’s 40% KO rate and local broadcast buzz marked it as a 2025 standout, teasing December’s U.S. card.

What’s Next?

Mayer eyes a Baumgardner unification in April 2026, likely in Las Vegas, to solidify her legacy. A win could spark multi-division talk. Spencer, targeting a March 2026 return, could face Jonas to rebuild. Her power ensures draw status. This Montreal thriller, boosted by a raucous crowd and a technical card, crowns Mayer as interim champ, with Spencer poised for a comeback.

On October 30, 2025, Mikaela Mayer outclassed Mary Spencer via unanimous decision, using precision and footwork to claim the interim WBO super featherweight title. Her 56% punch accuracy and Montreal masterclass set up a unification clash, amid Casino roars and a card full of heart. As Mayer targets Baumgardner and Spencer plots her return, this Canadian epic shines as a 2025 gem, promising more 130-pound drama.