ESPN's Adam Schefter is reporting that a pesky hamstring will keep the 6'1", 220-pound back from working out.
Schefter added, in an article on ESPN, that Lacy injured his hamstring running the 40-yard dash, and that "the doctors, trainers and performance trainers have indicated Lacy would not be able to resume training or be completely healthy to give a representative workout in time for the combine."
Presumably, the running back will still be around to answer any questions and talk to interested clubs. Also, there is a chance he will still work out before the draft. Schefter reports that Lacy is going to do his best to be ready to perform at Alabama's pro day on March 13.
Either way, the injury shouldn't be expected to hamper Lacy's draft stock too significantly.
Last year, as a junior, Lacy put his worth on vivid display while being the main rusher for the national champion Crimson Tide.
During the season, he rushed for 1,322 yards on 6.5 yards per carry and 17 touchdowns, and it's not like he was padding his numbers against powder-puff opponents.
Alabama played a difficult schedule, and Lacy was at his best when it mattered most.
The running back grabbed the eyes of the NFL world this past season as he torched Georgia in the SEC Championship for 181 yards and two touchdowns. He then followed that up with a 140-yard effort in the BCS title game.
Whether he is able to work out or not, Lacy is going to be one of, and likely the, first running back(s) off the board.