Robyn Troup went from Grammy Awards star to “American Idol” reject in three TV days. On Sunday, Troup, 19, of Houston sang with Justin Timberlake and rapper T.I. after winning the “My Grammy Moment” reality TV-style contest.

But on Tuesday’s “American Idol,” Troup was seen being rejected by the Fox talent contest’s judges in an episode that was taped before the Grammys.

There was a touch of irony in Troup’s dual appearances: the “Grammy Moment” contest smacked of “American Idol” and came a year after the Fox show pummeled the Grammys in the ratings when they aired opposite each other.

Moving the show away from “American Idol” paid off: More than 20 million people watched Sunday, up 18 percent from last year.

Credit: AP