Devon Still Fighting Like Hell To Get Back In NFL

We all know Devon Still's daughter, Leah, is a fighter ... but the 6'5" defensive end ain't no slouch either -- and tells TMZ Sports he's battling like crazy to get back in the NFL.

Still's currently a free agent after spending most of his 2016 season with the Houston Texans on injured reserve following a foot injury in Week 4.

But the 27-year-old says he's been training and rehabbing like a maniac -- and he's laser-focused on getting back on an NFL roster in 2017.