Jeremy Renner has been cast in a biopic about legendary boxer Rocky Marciano, the only heavyweight champion to ever retire with an undefeated record.

The film will be titled Undefeated: The Rocky Marciano Story and is approved by the Marciano family, reports Variety. It is being produced by Morris S. Levy (Seduced and Abandoned) and will be written by Samuel Franco and Evan Kilgore.

The writing duo penned Mayday 109, a script about President John F. Kennedy’s service during World War II. Deadline first reported that the Marciano film will be their next project.

Marciano was the heavyweight champion from 1952 to 1956 and died in 1969 in a plane crash. He retired with a record of 49-0.

Levy is still looking for a director, but Renner has signed on to star as Marciano.

Renner was just seen in Mission: Impossible - Rogue Nation and has Oscar nominations for The Town and The Hurt Locker. He will play Hawkeye again in Marvel’s Captain America: Civil War. He is currently working on Denis Villeneuve's Story of Your Life.