Josh Gordon is reportedly facing a one-year suspension after violating the NFL's substance-abuse policy for a third time.
The Cleveland Browns wide receiver was banned for 10 games during the 2014 regular season, following a failed test for marijuana.
That followed a previous drug violation in 2013 and Gordon now appears to be in line for a lengthy lay-off.
ESPN cited information from league sources on Sunday as they reported Gordon's latest infraction, while the news was also carried by the NFL's official website.
"Clearly we are very disappointed to hear the latest report regarding Josh," an unnamed Browns spokesperson is quoted as saying by ESPN. "At this point, due to the confidential nature of the NFL's substance-abuse policy, we have not been made aware by the league of a failed test.
"We are in the process of gathering more information and will provide further comment at the appropriate time."
Gordon is subject to testing for alcohol because he pleaded guilty to a DUI offense in North Carolina last September.
Under NFL rules, players with previous drug- or alcohol-related discipline on their records are subject to increased punishment at the commissioner's discretion.
Gordon was also suspended for the final game of Cleveland's 2014 season for violating team rules after catching 24 passes for 303 yards in five games. He led the NFL with 1,646 receiving yards in 14 games in 2014.