Mikaela Mayer has won world titles at super-featherweight, welterweight and now light-middleweight
Mikaela Mayer outpointed Mary Spencer in Canada to become a unified light-middleweight and a three-division world champion.
The 35-year-old American produced a dominant performance at the Montreal Casino, outboxing the hometown favourite over 10 rounds.
Judges scored the contest 100-90, 98-92 and 98-92 as Mayer claimed the WBA crown and the vacant WBC and WBO belts following trailblazer Cecilia Braekhus' retirement.
"I've won a WBO before but I've never had the WBA or WBC put around my waist, so this is extra special," Mayer said.
