Mikaela Mayer will fight Lucy Wildheart on Saturday in London after her original opponent, Christina Linardatou, was denied a license by the British Boxing Board of Control because of her prefight eye exam, a source confirmed to ESPN on Friday.

Mayer, an Olympian who fights out of Colorado Springs, Colorado, is making her lightweight debut after the first defeat of her pro career. The 32-year-old dropped a split decision to Alycia Baumgardner in a 130-pound title unification in October.

The bout against Wildheart, a Swede who fights out of England, will serve as chief support to the Joe Joyce-Zhang Zhilei heavyweight bout on ESPN+ (3 p.m. ET).

Mayer (17-1, 5 KOs) made three successful junior lightweight title defenses before she lost her two titles to Baumgardner. In Linardatou, Mayer was set to face a former champion, but she will still face a solid opponent on short notice in 30-year-old Wildheart (10-1, 4 KOs).

Wildheart's only pro defeat came against Estelle Mossely in 2019. Mayer is ESPN's No. 6 pound-for-pound women's boxer.

BoxingScene first reported on the change.