The move made Tuesday before the Marlins faced the New York Mets comes two days after Florida let Ross go to the San Francisco Giants on a waiver claim. Ross was the third-highest paid player on the cost-conscious club with a salary of $4.45 million.
Maybin is slated to bat seventh but Marlins manager Edwin Rodriguez sees him taking over the leadoff spot by the end of the week.
Maybin hit .338 this year in Triple-A with four homers and 23 RBIs in 33 games. He was hitting .225 for the Marlins with five homers and 19 RBIs in 51 games before being sent down on June 17.