Source: Mikaela Mayer to defend junior lightweight titles vs. Jennifer Han in April

Mikaela Mayer will defend her IBF and WBO junior lightweight titles on April 9 against Jennifer Han, a source told ESPN on Friday.

The fight will be Mayer's first since she defeated Maiva Hamadouche by unanimous decision on Nov. 5 to unify the IBF and WBO crowns. It will be Mayer's second straight fight as the main event.

The location has yet to be determined but will be in the United States.

Mayer (16-0, 5 KO) will make the third defense of her WBO title and first of the IBF crown.

Han (18-4-1, 3 NC, 1 KO), 38, last fought Sept. 4, when she lost a unanimous decision to undisputed lightweight champion Katie Taylor.

Before the Taylor fight, Han had not lost since 2014.