Devon Still says he's rooting hard for Marvin Lewis to get another shot to coach in the NFL -- telling TMZ Sports he'll always be grateful to Lewis for helping to save his daughter's life.
Remember, it was Lewis who kept Still on the Cincinnati Bengals roster back in 2014 when his daughter Leah was battling cancer ... so she could keep the team health insurance coverage.
The story made national news -- and people from all over the country bought Still's Bengals jersey to show their support for Devon, Leah and the Bengals organization.