The 21-year-old missed the start of the season with a foot injury, but has since added 455 rushing yards and four touchdowns.
The head coach told reporters: "The best thing about him is he doesn't pretend to know everything. He comes in the building every day ready and willing to learn.
"He listens well, and I think those are great skills and perspective to have to go along with his obvious physical talents."
The Steelers face the Baltimore Ravens tomorrow.