SAN DIEGO (AP) - NFL Players Association executive director DeMaurice Smith says the union is still concerned about San Diego Chargers team doctor David Chao even though he reportedly has been cleared by an independent panel.

In a statement to The Associated Press, Smith says neither the Chargers nor the NFL initiated an inquiry or provided oversight of Chao even though he has been found liable of malpractice.

At a pre-Super Bowl news conference, Smith called for Chao to be replaced as team doctor. The NFLPA filed a complaint.

Quoting a club source it did not identify, the U-T San Diego reported Sunday that three independent doctors ``totally exonerated'' Chao.

The NFL and the Chargers refused to confirm the report, citing confidentiality.

Chao hasn't returned calls and texts seeking comment.