Stephen A. Smith is nervous about the Steelers struggling this upcoming season since the roster has already suffered loss and Le'Veon Bell is facing a 4-game suspension for failure to take a drug test. (1:53)

PITTSBURGH -- Pittsburgh Steelers running back Le'Veon Bell took to the comments section of social media to defend himself in light of looming punishment for violation of the NFL's drug policy.

In response to a fan posting a picture on Instagram with a gas mask bong superimposed on Bell's head, Bell responded from his verified account: "I'm not going to miss games, trust me." This was not an official statement issued by Bell, whose agent, Adisa Bakari, has not responded to messages for comment.

Laremy Tunsil, a former Ole Miss left tackle, slipped to No. 13 overall in the 2016 NFL draft after an old video of him smoking marijuana from a gas mask surfaced online the night of the draft.

Bell, 24, faces a four-game suspension for missed drug tests, ESPN's Dan Graziano reported Friday. According to the NFL's collective bargaining agreement, a player can miss up to two drug tests without forfeiting games, but a third missed test triggers a four-game ban. The second missed test results in a fine of two game checks, but not the ability to play in those games.

"I'm gonna win the appeal...ppl have no idea what happened, but don't worry...let em hate," Bell wrote directly to a fan. "When I end up missin no games at all, ppl for sure gonna try to love me again and I'm only ridin with my LOYAL fans!!"

Last season, Bell served a two-game suspension for violation of the league's drug policy for possession and DUI in the Pittsburgh area in August 2014. Bell and former teammate LeGarrette Blount admitted to smoking marijuana after being pulled over on their way to the airport for a preseason road game. The NFL reduced Bell's original three-game ban on appeal.

Attempts to reach Bell have been unsuccessful. The Steelers and the NFL have declined comment.

Bell told reporters in June that he hadn't missed or failed any drug tests despite online rumors. Bell has been recovering from a knee injury that limited him in offseason. Bell said he plans to be healthy and ready for Week 1, if he gets the chance to show it.