KATE Walsh’s character in the new “Grey’s Anatomy” spin- off, “Private Practice,” will get a new best friend this fall.

Broadway diva Audra McDonald has been hired to replace Addison’s confidant, Merrin Dungey, who appeared in the show’s pilot last May.

Reports had been flying for weeks that the show’s creator Shonda Rhimes was looking for a new BFF because the chemistry between Walsh and Dungey had not been good.

McDonald is perhaps the most ecstatically reviewed Broadway star in recent memory. She has won a record four Tony Awards for both singing and acting roles in such shows as “Ragtime” and “Raisin in the Sun.”