The comedian will play Marty, the ex-husband of Veronica (Megan Mullally), when he appears in the show, TV Guide says.
The former couple have a difficult relationship, and when Veronica runs into Marty, she asks Cameron (Bret Harrison) to be her partner in a dance-off with him and his new girlfriend.
Willard previously starred in shows such as Roseanne, Mad About You, Back To You and Everybody Loves Raymond.
More recently, he has had guest roles in Modern Family, Raising Hope, The Closer and Rob.
Breaking In airs on Tuesdays at 9.30/8.30c on Fox.
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