Some NBA doctors have warned team officials about drafting Ohio State All-American Jared Sullinger because of a back issue, ESPN.com reported Monday.

Sullinger, who is projected to be a lottery pick in this year's NBA draft, underwent a series of medical tests at the NBA draft combine a week ago. Sources told ESPN.com the doctors who examined Sullinger were concerned with his back.

Several NBA team doctors reviewed the information and have told their front office members Sullinger's back problems could shorten his NBA career. Some have advised team officials not to draft him.

"He had a bulging area that was due to his hamstring and quads being so tight," Satch Sullinger, Jared's father, told ESPN.'s Andy Katz on Monday. "It pulled on his hip flexor and he's been taking care of it to loosen it. You can call it a red flag if you want. But it's tight hamstring and tight quads. He's been to doctors, he's doing yoga and deep tissue massage. The flexibility is helping take the pressure off the area.

"We've got nothing to hide. At this stage it's all about what they can't do. Jared is a skilled player. A two-time All-American. He can play."

Ohio State coach Thad Matta told Katz by text message Monday: "Jared is fine. He's moving better than I've ever seen him move.''