Tennessee Titans offensive tackle Taylor Lewan revealed on Twitter on Tuesday that he has failed a test for a banned supplement and will be suspended for four games.

But the 27-year-old Lewan says he did not ingest the substance knowingly and in a video message said that he took a polygraph test that supports his claim.

In the video, Lewan says the substance in question was Ostarine and he was informed of the positive test in a letter from the league several weeks ago.

"What really matters to me is that people know that I'm not a cheater," Lewan says in the video.

An emotional Lewan thanks his team for the support and fights tears apologizing to the Titans and their fans.

"I'm going to be better for this," Lewan says.

The native of Loomis, Calif., says he intends to release the results of his polygraph test shortly.

A three-time Pro Bowler, Lewan was taken with the 11th overall pick of the 2014 NFL Draft out of Michigan.

Heading into his sixth year a pro, Lewan has only missed two games over the past four seasons.