Carolina Panthers offensive lineman Lee Ziemba was suspended four games after testing positive for a banned stimulant, the Charlotte Observer reported Saturday.
Ziemba released a statement through his agent.
Ziemba, who is on injured reserve, said he never knowingly took a performance-enhancing substance. Ziemba, however, will not appeal the suspension.
The lineman will give up a fourth of his salary -- $116,250 -- in serving the suspension.
The substance for which Ziemba tested positive was not mentioned in his statement and the Observer was unable to contact him for further comment.
Ziemba said in the statement that he found out about the positive test in mid-September. He tore his lateral meniscus during training camp.
"I was extremely confused and upset when I was informed of this result since I have never knowingly ingested any performance-enhancing substance," he said. "My training regimen has included supplements that I carefully chose and believed to be free from any prohibited substance under the NFL/NFLPA policies.
"After extensive discussions and careful consideration of the terms of the NFL/NFLPA policies, I have chosen to be immediately accountable for the situation."
Panthers defensive tackle Andre Neblett tested positive during the offseason and was suspended for the first four games of this season.