Jaguars quarterback Blaine Gabbert left practice on a cart Monday with a right ankle sprain.
Offensive lineman Uche Nwaneri got pushed back while Gabbert was stepping up into the pocket, causing the ankle sprain.
"It was almost like the lineman's foot came right into his ankle," head coach Gus Bradley said. "Freak deal like that."
"I knew I had kicked him," Nwaneri said after practice. "Sometimes that type of stuff happens, but you don't want to have that type of stuff happen to your quarterback."
Nwaneri took the news hard because he said it's an offensive lineman's job to keep his quarterback upright and healthy.
"I take a lot of pride in blocking for my quarterback, so didn't like that I allowed that to happen. Obviously with the quarterback down, you're a little worried about that, so hopefully everything is good with him."
The extent of the injury is still unknown. The Jaguars have an off-day Tuesday before returning to practice at 9:55 a.m. Wednesday.