Former two-division champion Mikaela Mayer became a unified champion at 154 pounds with a one-sided unanimous decision over WBA champion Mary Spencer on Thursday night, claiming the vacant WBC and WBO titles in the process.
The fight headlined a Top Rank card at Casino de Montreal in Montreal.
Mayer (22-2, 5 KOs) dominated from the opening bell with relentless pressure and impressive cardio. Spencer (10-3, 6 KOs) had no answers despite being the naturally bigger fighter and instead relied heavily on attempting to counter advances. She was unable to slow Mayer down. One judge scored the bout a shutout for Mayer 100-90, with two other judges scoring it 98-92.
Oshae Jones currently holds the IBF title, should Mayer decide to pursue undisputed status at junior middleweight. Or she can move back down to welterweight and chase three-belt holder Lauren Price.
“I think the most important thing is that I have options,” Mayer said. “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.”
Mayer made the move to junior middleweight after holding titles at super featherweight and welterweight. After starting her career 17-0 and becoming the unified super featherweight title, she fell short in a highly anticipated unification fight with Alycia Baumgardner in 2022. Mayer bounced back with two wins at lightweight in 2023 but dropped a close decision to Natasha Jonas in her first attempt to capture welterweight gold. She would eventually grab a world title at welterweight by defeating Sandy Ryan for the WBO title in September 2024 and making a successful defense in the rematch in March.
Moving up in weight again, Mayer was expected to have some trouble with the naturally bigger Spencer. However, it was Mayer who quickly settled into the role of the bully, working behind the jab and plowing forward with her offense. Spencer was content to fight off her backfoot and look for opportunities to counter with her right hand.
Mayer, 35, was the busier of the two, rumbling forward and ambushing Spencer with her offense in the early rounds. Spencer managed to slip in chopping right hands but was unable to thwart the pressure cooker that Mayer placed her in.
Spencer, 40, did her best work in Round 5, picking off Mayer with right hands and catching her with a thudding uppercut. But Mayer’s chin was impressive, and she had little trouble absorbing the power of Spencer.
Mayer got back into her rhythm in the following round and swarmed Spencer with her offense. In Round 8, Mayer broke through and drilled Spencer with a straight right hand that appeared to stagger her opponent. Mayer continued to slam combinations into Spencer in Round 9, with a right hand breaking her composure. The punishment continued in the final round as Mayer closed the show impressively, violently slamming power shots into Spencer until the final bell.
