Titans' Lewan takes polygraph after positive test

Lewan facing suspension for failed drug test (1:05)

Adam Schefter reacts to Titans lineman Taylor Lewan announcing that he is facing a suspension for a failed drug test, but Schefter says the situation is still fluid. (1:05)

NASHVILLE, Tenn. -- Tennessee Titans left tackle Taylor Lewan is facing a suspension after a test came up positive for the banned substance ostarine, according to a post he made via social media Wednesday.

A source told ESPN's Adam Schefter that Lewan's A sample tested positive this summer but that the results of his B sample had not come back yet. If the samples match, he would face a four-game suspension.

Lewan, who will dispute the test results in an appeal, said he didn't knowingly use a banned substance.

"I've never taken anything that would cheat the game. I'm so sorry to the Tennessee Titans," Lewan said before pausing, taking a deep breath and wiping his eyes. "I'm sorry to the Titans, to the fans, that I won't be there for four games. I've never cheated myself, and I never want you guys to feel cheated. And I'm sorry. But I'm going to be better for this. I'm going to come back."

Lewan also posted apparent polygraph results on Instagram, and he said his supplements were tested by a third party.

He became the league's highest-paid offensive lineman last season after signing a five-year, $80 million deal that included $50 million guaranteed.

The Titans open up the season with a tough stretch of games that includes the Browns, Colts, Jaguars and Falcons.