Hart, who enrolled early and was impressive in spring practice, is scheduled to undergo surgery later this week after suffering the injury during voluntary workouts, according to the sources.
Hart's Dr. Phillips (Fla.) High School running backs coach, Riki Smith, told the Orlando Sentinel that Hart tore his anterior cruciate ligament during a 7-on-7 passing drill. Smith said Hart would begin rehabilitating his knee immediately and hoped to be back in seven to 10 months.
Losing Hart puts a dent in the Crimson Tide's backfield depth. He impressed the Alabama coaches in the spring with his ability to do several different things and was a candidate to be Alabama's third-down back. The 5-foot-9, 187-pound Hart was also vying to become the lead punt returner.
One of the top running back prospects in the country last year, Hart was an ESPNU 150 selection and rated by ESPN as the No. 8 running back nationally.
Chris Low covers the SEC for ESPN.com.