USA TODAY Sports Eugene Monroe

NFL rules ban its players from using marijuana. But one player is calling on the league to reconsider that policy -- and his motivations aren't recreational.

According to Eugene Monroe, the NFL creates a need for marijuana use among many of its players. "Your job automatically gives you the symptom of chronic pain," the Ravens offensive tackle tells CNN. "You're hitting each other as hard as possible every single day in practice. Your body is in pain a lot of [the] time."

Other chronic pain medications, such as opioids, present serious risks, including possible addiction. By contrast, marijuana doesn't. In that regard, it could be a safer alternative to pain medications that are currently allowed by the league.

Recent research has advocated for greater use of marijuana as a medicinal substance, particularly for chronic pain. But during a press conference prior to the Super Bowl, NFL commissioner Roger Goodell gave no indication that the league was reconsidering its stance.

"I agree there has been changes, but not significant enough changes that our medical personnel have changed their view," Goodell said. "Until they do, then I don't expect that we will change our view."

Monroe also noted that the league could help push research forward that could lead to substance use reform, but the NFL has expressed no interest in doing so.

What's holding the NFL back? The body of research might have something to do with it. Another theory is that the NFL's resistance to marijuana is branding-related. Were the league to become the first American pro sports league to allow marijuana use among its players, it could affect the public image of the league.

And as we all know, nothing matters to the NFL more than its brand.

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