Lionel Richie has bowed out of the upcoming ABC series, Duets. His representative cites "personal scheduling conflicts." Richie will be replaced by R&B singer John Legend, according to Entertainment Weekly. As previously announced, Jennifer Nettles of Sugarland, Kelly Clarkson and Robin Thicke will serve as the series' three other mentors. On the show, which is expected to air this summer, the four mentors will be seeking aspiring talent to perform duets in front of a live studio audience. Richie released an album of duets with country artists, Tuskegee, in March.